Forces and acceleration, Physics multiple choice questions

which force produces the smallest torque?

20.0N perpendicular to the center of rotation at a radius of 1.0 m

10.0 N perpendicular to the center of rotation at a radius of 1.5 m

20.0 N perpendicular to the center of rotation at a radius of 0.5 m

10.0 N perpendicular to the center of rotation at a radius of 0.25 m

a car decelerates from 20 m/s to 10 m/s. which of the following statements is true?

1.No net torque acts on the wheels at all.

2.You cannot tell from the information given

3.A net torque acts on the wheels opposite their direction of motion

4.a net torque acts on the wheels in their direction.

What is the frequency of motion of a 0.67 m long pendulum?

0.61 hz

0.43 hz

2.33 hz

1.6 hz