Circular Motion

Q.

Give two examples of bodies having non-uniform motion.

Q.

Give examples of uniform and non-uniform speed.

Q.

Describe motion in a straight line?

Q.

What are the characteristics of motion?

Q.

A circular running track is $\frac{1}{4}mile$ long. Elena runs on this track, completing each lap in $\frac{1}{20}$ of an hour. What is Elenas running speed? Include the unit of measure.

Q. A person is running on a horizontal circular track of radius R. In the first round, he runs with speed v and takes time t. If he takes time 2t covering the same track in the second round, then his speed will be
(i) $\frac{v}{2}$
(ii) 2v
(iii) $\frac{\pi R}{t}$
(iv) $\frac{\pi R}{t}$

1. (ii) and (iii)
2. (i) and (iii)
3. (i) and (iv)
4. (ii) and (iv)

Q. Give two examples of circular periodic motion. [2 MARKS]

Q. A particle is revolving on a circular path with a constant speed. If its speed and radius of the path are doubled, then its angular speed will

1. Remain unchanged
2. Gets doubled
3. Gets quadrupled
4. Gets halved

Q.

Speed can be uniform even if velocity is not uniform.

1. True
2. False

Q. Which of the following examples describe the body to be in a circular motion?

1. A boy riding a Ferris wheel
2. Train moving on a straight track
3. An oscillating tuning fork
4. A child on a swing

Q. An object follows curved path. Which of the following quantities may remain constant during the motion

1. speed
2. velocity
3. magnitude of acceleration
4. acceleration

Q.

The following quantities may remain constant during uniform circular motion :

1. magnitude of acceleration

2. acceleration

3. speed

4. velocity

Q. A car is moving with speed $3.5\text{m/s}$. If the radius of its tyre is $0.35\text{m}$, then calculate the angular velocity of the wheel of the car.

1. $20\text{rad/s}$
2. $11\text{rad/s}$
3. $10\text{rad/s}$
4. $25\text{rad/s}$

Q. The wheel of a cycle has a diameter $1\text{m}$. If the wheel has an angular speed of $5\text{rad/s}$, then calculate the speed of cycle in $\text{m/s}$.

1. $5\text{m/s}$
2. $2.5\text{m/s}$
3. $7\text{m/s}$
4. $7.5\text{m/s}$

Q. Assertion :It is possible to accelerate even if you are travelling at constant speed. Reason: In the uniform circular motion, even if the particle has the constant speed, it has an acceleration.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Study the given paragraph(s) and answer the following questions.

A particle is moving along a circular track of radius $3.5\mathrm{m}$ with a constant speed $4{\mathrm{ms}}^{-1}$. Answer the following for the motion of the particle.

How much time will it take to complete one complete round ?

1. $5.5s$

2. $11s$

3. $22s$

4. $3.5s$

Q.

A cyclist goes around a circular track once every 2 mins. If the radius of the circular track is 110m, Calculate the speed of the cyclist.

Q. The angular velocity of the second's hand of a watch is

1. $\frac{\pi }{60}$ rad/sec
2. $\frac{\pi }{30}$ rad/sec
3. $60\pi$ rad/sec
4. $30\pi$ rad/sec

Q. Choose the correct statement for a body undergoing a uniform circular motion.

1. Its velocity changes but speed remains the same.
2. Its speed changes but velocity remains the same.
3. Both speed and velocity changes.
4. Both speed and velocity do not change.

Q.

Match the following:
$\begin{array}{cc}\text{Column I}& \text{Column II}\\ 1.\text{A car moving on a straight road}& A)\text{Oscillatory Motion}\\ 2.\text{A mark made on the blade of a rotating fan}& B)\text{Circular Motion}\\ 3.\text{Motion of a swing}& C)\text{Rectilinear Motion}\end{array}$

Select the appropriate option.

1. 1 - C, 2 - A, 3 - B

2. 1 - C, 2 - B, 3 - A

3. 1 - A, 2 - B, 3 - C

4. 1 - B, 2 - A, 3 - C

Q.

A boy is whirling a stone tied with a string in a horizontal circular path. If the string breaks, the stone

1. will continue to move in the circular path

2. will move along a straight line towards the centre of the circular path

3. will move along a straight line tangential to the circular path

4. will move along a straight line perpendicular to the circular path away from the boy

Q. In a uniform circular motion, the direction of velocity at any point is _____.

1. towards the centre
2. along the circumference
3. random
4. along the tangent