Practice Quiz 10 , Physics 101, General Physics

Practice Quiz 10
1)  A fan is turned off, and its angular speed decreases from 10.0 rad/s to 6.3 rad/s in 5.0 s. What is the
magnitude of the angular acceleration of the fan?
A) 0.74 rad/s
2
 
B) 0.37 rad/s
2
C) 11.6 rad/s
2
D) 1.16 rad/s
2
Answer: A
2)  A wheel that is rotating at 33.3 rad/s is given an angular acceleration of 2.15 rad/s
2
. Through what angle
has the wheel turned when its angular speed reaches 72.0 rad/s?
A) 83.2 rad
B) 697 rad
C) 66.8 rad
D) 948 rad
Answer: D
3)  A wheel rotates through an angle of 320e as it slows down from 78.0 rpm to 22.8 rpm. What is the
magnitude of the average angular acceleration of the wheel?
A) 5.46 rad/s
2
B) 6.50 rad/s
2
C) 8.35 rad/s
2
D) 10.9 rad/s
2
Answer: A
4)  Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation
than child B. Which child has the larger angular speed?
A) Child A
B) Child B
C) They have the same angular speed.
D) There is not enough information given to answer the question.
Answer: C
5)  Earth circles the sun at a distance of 1.50 × 10
11
 m. What is the tangential speed of Earth in its orbit?
A) 29900 m/s
B) 14900 m/s
C) 59800 m/s
D) 7470 m/s
Answer: A
6)  A child is riding a merry-go-round which completes one revolution every 8.36 s. The child is standing
4.65 m from the center of the merry-go-round. What is the magnitude of the centripetal acceleration of the
child?
A) 6.84 m/s
2
 
B) 2.63 m/s
2
C) 0.0664 m/s
2
D) 0.696 m/s
2
Answer: B
7)  Earth's radius is 6.38 × 10
6
 m, and it completes one revolution every day. What is the magnitude of the
centripetal acceleration of a person standing on the equator?
A) 0.00844 m/s
2
B) 0.00343 m/s
2
C) 0.0337 m/s
2
D) 0.000854 m/s
2Answer: C
8)  A Ferris wheel with a radius of 8.0 m rotates at a constant rate, completing one revolution in 30.0 s.
What is the apparent weight of a 60.0-kg passenger when she is at the top of the wheel?
A) 589 N
B) 568 N
C) 615 N
D) 325 N
Answer: B
9)  A Ferris wheel with a radius of 16.0 m rotates at a constant rate, completing one revolution in 30.0 s.
What is the apparent weight of a 60.0-kg passenger when she is at the bottom of the wheel?
A) 589 N
B) 562 N
C) 631 N
D) 852 N
Answer: C
10)  A child is riding a merry-go-round, which has an instantaneous angular speed of 1.25 rad/s and an
angular acceleration of 0.745 rad/s
2
. The child is standing 4.65 m from the center of the merry-go-round.
What is the magnitude of the acceleration of the child?
A) 8.05 m/s
2
B) 7.27 m/s
2
C) 2.58 m/s
2
D) 3.46 m/s
2
Answer: A
11)  A scooter has wheels with a diameter of 120 mm. What is the angular speed of the wheels when the
scooter is moving forward at 6.00 m/s?
A) 47.7 rpm
B) 955 rpm
C) 50.0 rpm
D) 100 rpm
Answer: B
12)  A soccer ball whose radius is 11 cm rolls a distance of 10 m in 3.50 s. What is the angular speed of the
ball?
A) 13 m/s
B) 26 m/s
C) 39 m/s
D) 52 m/s
Answer: B