Physics College

## Answers

**Answer 1**

Answer: the speedometer indicates the speed of a vehicle.

## Related Questions

what is the wavelength of waves at the beach if they have a frequency of 0.3 Hz and they move at 7.1 m/s?

### Answers

Answer:

23.67 m

Explanation:

We are given;

Frequency; f = 0.3 Hz

Speed; v = 7.1 m/s

Now, formula to get the wavelength is from the wave equation which is;

v = fλ

Where λ is wavelength

Making λ the subject, we have;

λ = v/f

λ = 7.1/0.3

λ = 23.67 m

What happens to the electrons when you rub a balloon in your hair

### Answers

**Answer:**

When you rub a balloon on your head, electrons move from the atoms and molecules in your hair onto the balloon. Electrons have a negative charge, so the balloon becomes negatively charged, and your hair is left with a positive charge.

**Explanation:**

Newton's 3rd Law is based on what type of forces?

### Answers

**Answer: His third law states that for every action (force) in nature there is an equal and opposite reaction. In other words, if object A exerts a force on object B, then object B also exerts an equal and opposite force on object A.**

**Explanation:**

**Explanation:**

According to Newton's third law of motion, whenever two objects interact, they exert equal and opposite forces on each other. This is often worded as 'every action has an equal and opposite reaction'.

3. The SI unit in which K.E is often measured is the ................................................

give units

### Answers

**Answer:**

Joules.

**Explanation:**

Kinetic energy can be defined as an energy possessed by an object or body due to its motion.

Mathematically, kinetic energy is given by the formula;

[tex] K.E = \frac{1}{2}MV^{2}[/tex]

Where;

K.E represents kinetic energy measured in Joules. M represents mass measured in kilograms. V represents velocity measured in metres per seconds square.

Kinetic energy is a form of energy and is always measured in Joules.

Hence, the S.I unit in which K.E is often measured is the Joules.

how do newton's 3 laws of motion effective everyday life?

### Answers

Answer:

Examples of Newton's third law of motion are ubiquitous in everyday life. For example, when you jump, your legs apply a force to the ground, and the ground applies and equal and opposite reaction force that propels you into the air. Engineers apply Newton's third law when designing rockets and other projectile devices.

Explanation:

A3 kg mass takes some impulse in order increase its velocity from 11

m/s to 25 m/s. Calculate the impulse it took.

### Answers

**Answer:**

JAKSJAKZNPWLAQJZOAKZONZPW

THE ANSWER IS FAILURE

Which list below contains only ionic compounds?

A. CaCl2, H2O, LIF

B. CO2, K20, P4010

C. LiF, CaCl2, Mgo

D. NO2, Mgo, CuCl2

### Answers

**Answer:**

**C. LiF, CaCl2, MgO**

**Explanation:**

Ionic compound: It is that compound which consist of negative and position ions and held together by electrostatic force of attraction.

The ionic compound is neutral.

The ionic compound formed between metal and non-metal.

Covalent compound: It is that compound in which sharing of electrons between two atoms occur.

A.[tex]CaCl_2,H_2O,LiF[/tex]

H2O is not ionic compound. It is polar covalent.

Therefore, it does not contain only ionic compounds.

B.CO2,K2O,P4O10

CO2 and P4O10 are not ionic .It is covalent.

Therefore, it does not contain only ionic compounds.

C. LiF,CaCl2 ,MgO

All compounds are ionic because in given compounds one ion is negative and one is metal (positive).

Therefore, it contains only ionic compounds.

D.NO2,MgO,CuCl2

NO2 is not ionic.

Therefore, it does not contain only ionic compounds.

**Option C is correct.**

a virtual image is formed by

a) simple microscope b) telescope c) the ordinary camera d) a slide projector in a cinema hall

### Answers

**Answer: ordinary camera**

**Explanation:**

What happens when a mixture is formed?

### Answers

physical properties change

hope that helps

**Answer:**

**Explanation:**

A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad, salt water and a mixed bag of M&M's candy.

An object is traveling with a constant speed of 35 m/s. How long does it take to cover 770 m?

### Answers

**Answer:**

22 s

**Explanation:**

time = distance / velocity

We know that distance = 770 m and velocity = 35 m/s.

t = d / v

t = 770 m / 35 m/s

t = 22 s

It takes 22 seconds to cover 770 m. Hope this helps, thank you !!

A student measures that 81,500 J of thermal energy were added to 0.5 kg of water. If the specific heat of water is 4,184 J/kg 0C, what was its change of temperature?

### Answers

**Answer:**

[tex]\Delta T=38.95^{\circ} C[/tex]

**Explanation:**

Given that,

Heat measured, Q = 81500 J

Mass of water, m = 0.5 kg

The specific heat of water is 4,184 J/kg °C

**We need to find the change in temperature. The heat measured is given by :**

[tex]Q=mc\Delta T[/tex]

Where

[tex]\Delta T[/tex] is the change in temperature

[tex]\Delat T=\dfrac{Q}{mc}\\\\\Delat T=\dfrac{81500}{0.5\times 4184 }\\\\\Delta T=38.95^{\circ} C[/tex]

**So, the change in temperature is **[tex]38.95^{\circ} C[/tex].

Question 10 (1 point)

Which of the following statements about an object with a positive acceleration is always true?

An object with a positive acceleration is always increasing its speed.

An object with a positive acceleration is always increasing its velocity.

An object with a positive acceleration is always decreasing its speed.

An object with a positive acceleration is always decreasing its velocity.

### Answers

**Answer:**

An object with a positive acceleration is always increasing it's velocity.

A child throws a ball with an initial speed of at an angle of 40.0° above the horizontal. The ball leaves her hand 1.00 m above the ground and experience negligible air resistance. (a) What is the magnitude of the ball's velocity just before it hits the ground? (b) At what angle below the horizontal does the ball approach the ground?

### Answers

Complete Question

A child throws a ball with an initial speed of 8.00 at an angle of 40.0° above the horizontal. The ball leaves her hand 1.00 m above the ground and experience negligible air resistance. (a) What is the magnitude of the ball's velocity just before it hits the ground? (b) At what angle below the horizontal does the ball approach the ground?

Answer:

[tex]v=9.16m/s[/tex]

[tex]\theta=48.1 \textdegree[/tex]

Explanation:

From the question we are told that

Angle of ball [tex]\angle=40 \textdegree[/tex]

Height of ball h=1m

Generally the equation for vertical component is mathematically given by

[tex]v_y=vsin \theta[/tex]

[tex]v_y=8sin 40 \textdegree[/tex]

[tex]v_y=5.14m/s[/tex]

Generally the equation for horizontal component is mathematically given by

[tex]v_x=vcos \theta[/tex]

[tex]v_x=8cos 40 \textdegree[/tex]

[tex]v_x=6.12m/s[/tex]

Generally the equation for vertical displacement of ball is mathematically given by

[tex]y=1+v-yt-\frac{1}{2}gt^2[/tex]

[tex]0=1+5.14t-\frac{1}{2}*9.87*t^2[/tex]

[tex]t=1.22sec[/tex]

[tex]v_yt=v_yt-gt[/tex]

[tex]5.14-(9.8*1.22)=-6.816m/s[/tex]

[tex]v_yt=-6.816m/s[/tex]

Generally the velocity of ball before it hits the ground is mathematically given by

Magnitude

[tex]v=\sqrt{6.12^2 +(-6.816)^2}\\[/tex]

[tex]v=9.16m/s[/tex]

Direction of ball

[tex]\theta=tan^{-1}(\frac{-6.816}{6.12} )[/tex]

[tex]\theta=48.1 \textdegree[/tex] beneath the horizontal

PLE.ASE HURRY DUE IN 20 MINWhat is the independent variable (the variable that was changed ) in this investigation? How was it measured? Include the units in your answer.

Answer:

What was the dependent variable (the variable that changed because of the independent variable) in this investigation? How was it measured? Include the units in your answer. The variables Car 1 3.64 3.54 3.69 Car 2 3.24 3.47 3.36 Meters Each car traveled 2.5

### Answers

**Answer:**

Do you want the independent or dependent? Independent is the Car and the dependent is the meters traveled.

**Explanation:**

**Answer:**

sample answer

In this situation, elevation is dependent on time. So, the dependent variable is elevation in feet.

**Explanation:**

Explain temperature and how it is measured.

PLEASE PLEASE HELP ME!! I NEED IT AND PLEASE DO IT IN YOUR OWN WORDS!! PLEASE I JUST NEED IT!! OWN WORDS PLEASE!!

### Answers

**Answer:**

temperature is the degree of heat in a item or object and is measured by a thermometer.

**Explanation:**

The north pole of a magnet is brought near to the current-carrying solenoid.

State whether the north pole is attracted or repelled by the solenoid. Explain why.

### Answers

**Answer:**

The north and south pole of a solenoid depends on two factors. One, the direction of the current flow and two, the direction of the winding (clockwise or counter-clockwise). ... If clockwise in relation to the positive wire then is the south pole, if anti-clockwise then is the north pole.

**Explanation:**

The north and south pole of a solenoid depends on two factors. One, the direction of the current flow and two, the direction of the winding (clockwise or counter-clockwise). ... If clockwise in relation to the positive wire then is the south pole, if anti-clockwise then is the north pole.

Which of the following laws explains why a net force of 950,000 N is needed at takeoff to accelerate the

530,000 kg Atlas V rocket carrying the rover at a rate of 1.8 m/s2?

A

Newton's third law of motion

B

conservation of momentum

С

Newton's second law of motion

D

Newton's first law of motion

### Answers

**Answer:**

Newton's second law of motion

Momentum = the product of mass and velocity

= unit is kg m/s

Parti: Find the momentum in each picture:

Moss = 2500 kg

Velocity = 25m's

Mass=320

Velocity=12ms

Moss - 85 kg

speed=&m's

Changing the Momentum:

To change the momentum of an object, a

must be applied to the object. This action will

cause the

of the object to change. When the velocity increases, the momentum will

When the velocity

the momentum will decrease. The change in the

momentum of the object is called IMPULSE.

### Answers

Answer:62500,3840

Explanation:

What is the frequency of a wave that has a wavelength of 0.20 m and a speed of 22 m/s

### Answers

**Answer:**

The frequency of the wave would come out to be 110 Hz.

Frequency is the number of completed wave cycles per second. By using the simplest frequency equation, f = 1 / T, you get the answer I provided above.

Please show your work.

13. Convert 97 degrees fahrenheit to degrees celsius.

Need this now

### Answers

**Answer:**

(97°F − 32) × 5/9 = 36.111°C

**Explanation:Hope this helped**

Review. As it passes over Grand Bahama Island, the eye of a hurricane is moving in a direction 60.08 north of west with a speed of 41.0 km/h. (a) What is the unit-vector expression for the velocity of the hurricane

### Answers

**Answer:**

**Velocity = -20.45 i + 35.54 j km/h**

**Explanation:**

**given data **

speed v = 41.0 km/h

direction = 60.08 north of west

**solution**

first we get here Speed in west direction that is express as

Speed in west direction = v × cos(60.08) ..........................1

Speed in west direction = 41 × cos(60.08)

**Speed in west direction = 20.45 km/h**

now we get Speed in north direction that is

Speed in north direction = v × sin(60.08) ............................2

Speed in north direction = 41 × sin(60.08)

**Speed in north direction = 35.54 km/h**

so Velocity will be here

**Velocity = -20.45 i + 35.54 j km/h**

A capacitor and an electric source are both connected to a light bulb. If the power source is momentarily disconnected from the circuit, what will happen to the light bulb?

Group of answer choices

It will get brighter because the capacitor is providing more power than the electrical source.

It will no light because the electric source is the only thing required to power the bulb.

It will stay momentarily lit because the capacitor is supplying a voltage.

It will flash on and off because of the unstable power.

### Answers

**Answer:**

It will no light because the electric source is the only thing required to power the bulb.

**Explanation:**

An ice skater of mass 82 kilograms stands at rest in her skates on the ice rink. Someone throws a 5-kg ball at her at a speed of 17.4 m/s and she catches it. At what speed will she(and the ball) slide backwards?

### Answers

**Answer:**

1 m/s

**Explanation:**

I showed my work in the picture attached.

This web page helped me solve this problem and understand inelastic collisions a little better:

https://byjus.com/physics/inelastic-collision/

She **slide**(and the ball) **backwards **at the speed of **1m/s **when she **catches **the **ball **of 5-kg coming at **speed **of 17.4 m/s.

What is momentum ?

**Momentum **is defined as **mass **times **velocity**. it tells about the moment of the body. it is denoted by **p **and expressed in **kg.m/s. **mathematically it is written as **p = mv.** A body having **zero velocity** or **zero mass **has **zero momentum**. its dimensions is [M¹ L¹ T⁻¹].

Momentum is **conserved **throughout the motion.

According to conservation law of momentum** initial momentum** is equal to** final momentum. **

Given,

mass of the skater m₁ = 82 kg

mass of the ball m₂ = 5kg

initial velocity of the ball v'₂ = 17.4 m/s

initial velocity of the skater v''₂= v'₁= 0

final velocity of the ball & skater = v''₁ = ?

According to law of **conservation of momentum,**

initial momentum = final momentum

m₁v'₁ +m₂v'₂ = m₁v₁'' + m₂v''₂

putting all values in the equation.

0+ 5×17.4 = 82×v₁'' + 5×v₁''

v₁''(82+5) = 87

v₁'' = 1 m/s

Hence he(and the ball) slide backwards at **1m/s**

To know more about** conservation of momentum **click :

https://brainly.com/question/24301052

#SPJ2

How is an electromagnetic field produced? Please I need answers

### Answers

**Answer:**

by potential difference and electron gun

**Explanation:**

a magnetic field is produced whenever an electrical charge is in motion. The spinning and orbiting of the nucleus of an atom produces a magnetic field as does electrical current flowing through a wire. The direction of the spin and orbit determine the direction of the magnetic field.

**Answer:**

Electromagnetic field can be produced by the **superposition **of electric field and magnetic field.

**Explanation:**

**What is superposition ?**

When two or waves propagate in a medium without affecting each other , then at any instant the displacement of a particle will be equal to the vectorial sum of the displacements due to the waves.

Electromagnetic field can be produced by electric arc.It cab be produced by LC Circuits.

Hence Electromagnetic field can be produced by **L-C CIRCUITS.**

For more details , read it too-

**https://brainly.com/question/17057080**

**#SPJ2**

An unfortunate astronaut loses his grip during a spacewalk and finds himself floating away from the space station, carrying only a rope and a bag of tools. First he tries to throw a rope to his fellow astronaut, but the rope is too short. In a last ditch effort, the astronaut throws his bag of tools in the direction of his motion, away from the space station. The astronaut has a mass of ma=102 kgma=102 kg and the bag of tools has a mass of mb=10.0 kg.mb=10.0 kg. If the astronaut is moving away from the space station at vi=2.10 m/svi=2.10 m/s initially, what is the minimum final speed vb,fvb,f of the bag of tools with respect to the space station that will keep the astronaut from drifting away forever?

### Answers

**Answer:**

The answer is "[tex]2.352 \ \frac{m}{s}[/tex]"

**Explanation:**

[tex]\to mass(m_1)=102 \ kg\\\\\to mass(m_2)=10 \ kg \\\\\to v=2.10\ \frac{m}{s}\\\\[/tex]

**momentum before:**

[tex]\to p=(m_1+m_2)v[/tex]

** **[tex]=(102+10)2.10\\\\=(102\times 2.10 +10 \times 2.10)\\\\=214.2+21\\\\=235.2[/tex]

**momentum After:**

[tex]\to p=(m_1+m_2)v[/tex]

** **[tex]=(102\times 0 +10 \times v)\\\\ =(0 +10v)\\\\=10v\\[/tex]

**Calculating the conservation of momentum:**

[tex]\to \text{momentum before = momentum After}[/tex]

[tex]\to 235.2=10v\\\\\to v= \frac{235.2}{10}\\\\ \to v=2.352 \ \frac{m}{s}[/tex]

A person in car slides to the right when going through a very sharp left turn on the highway. Is that law of inertia or law of acceleration?

### Answers

**Answer:**

Inertia :)

**Explanation:**

This circuit has more than one loop. When one light goes out, the

others stay on.

A.open circuit

B.series circuit

C.parallel circuit

D.closed circuit

### Answers

**Answer:**

Parallel circuit

**Explanation:**

A parallel circuit has a direct current allowing it to go back and forth making it have more pathways and loops. if one light bulb goes out the pathways will allow the electricity to still flow inti the other light bulbs.

A boy starts from point A and walks 3 meters toward the north, then turns around and walks 6 meters toward the south.

What was the distance traveled by the boy?

### Answers

**Answer:**

Total distance traveled = 9 m

**Explanation:**

**Given:**

Distance travel towards north = 3 meter

Distance travel towards south = 6 meter

**Find:**

Total distance traveled

**Computation:**

Total distance traveled = Sum of total distance

Total distance traveled = Distance travel towards north + Distance travel towards south

Total distance traveled = 3 m + 6 m

**Total distance traveled = 9 m**

What attitudes and actions can group leaders take in trying to establish trust within a group during the initial stage of group development? How is each attitude and action important in the process of initiating trust?

### Answers

**Answer:**

i dont know!

**Explanation:**

The height of the observation deck of the Empire State Building is 380 m. If you dropped a penny from this height, how fast would it be going when it struck the ground? Assume there is no air resistance.

### Answers

**Given :**

The height of the observation deck of the Empire State Building is 380 m.

A penny is dropped from this height.

**To Find :**

How fast would it be going when it struck the ground.

**Solution :**

Initial speed, u = 0 m/s.

We know, speed of object free falling is given by :

[tex]v^2 - u^2 = 2gh\\\\v = \sqrt{2gh}[/tex]

Here, g = 9.8 m/s² = acceleration due to gravity.

Putting all values in above equation, we get :

[tex]v = \sqrt{2\times 9.8\times 380}\ m/s\\\\v = 86.30\ m/s[/tex]

**Hence, this is the required solution.**