Rotational Motion

A 0.12-m-radius grinding wheel takes 5.5 s to speed up from 2.0 rad/s to 11.0 rad/s. What is the wheel's average angular acceleration?

• 9.6 rad/s/s

• 4.8 rad/s/s

• 3.1 rad/s/s

• 1.6 rad/s/s

A fan blade, initially at rest, rotates with a constant acceleration of 0.025 rad/s². What is the time interval required for it to reach a 4.2 rad displacement after starting from rest   

• 1.8 s
• 2.0 s
• 16 s
• 18 s

Tags

NGSS.HS-PS2-1

A gear spins at a rate of 400 revolutions/minute. Which choice is closest to its angular speed in radians/second?

• 6.67 rad/s

• 2500 rad/s

• 41.9 rad/s

• 20.9 rad/s

A tire of 68cm in diameter travels 9.2km. How many revolutions does it make?

• 43.00 rads

• 567 revs

• 4300 revs

• 68cm

A 0.50-kg toy is attached to the end of a 1.0-m very light string.  The toy is whirled in a horizontal circular path on a frictionless tabletop.  If the maximum tension that the string can withstand without breaking is 350 N.  What is the maximum speed the mass can have without breaking the string?

• 700 m/s
• 26 m/s
• 13 m/s
• 19 m/s

Tags

NGSS.HS-PS2-1

A 2.0-kg ball is moving with a constant speed of 5.0 m/s in a horizontal circle whose diameter is 1.0 m. What is the magnitude of the net force on the ball?

• 50 N
• 20 N
• 0 N
• 100 N

Tags

NGSS.HS-PS2-1

A small 175-g ball on the end of a light string is revolving uniformly on a frictionless surface in a horizontal circle of diameter 1.0 m.  The ball makes 2.0 revolutions every 1.0 s. What are the magnitude and direction of the acceleration of the ball?

• 79.0 m/s²
• 35.0 m/s²
• 13.8 m/s²
• 87.5 m/s²

Tags

NGSS.HS-PS2-1

A cave dweller rotates a pebble in a sling with a radius of 0.30 m counterclockwise through an arc length of 0.96 m. What is the angular displacement of the pebble?

• 1.6 rad
• -1.6 rad
• 3.2 rad
• -3.2 rad

A bucket on the circumference of a water wheel travels an arc length of 18 m. If the radius of the wheel is 4.1 m, what is the angular displacement of the bucket?

• 1.0 rad
• 4.4 rad
• 3.7 rad
• 2.3 rad

What is the approximate angular speed of a wheel rotating at a rate of 5.0 rev/s?

• 3.2 rad/s
• 1.6 rad/s
• 16 rad/s
• 31 rad/s