A girl sits on a tire swing that is attached with a rope that is 2.10 m in length. Her dad pushes her with a speed of 2.5 m/s. If the centripetal force is 88.0 N, what is
the girl's mass?

m=88/2.97=29.63kg

Explanation

Use 2.10 m as the radius

v=2.5m/s

Fc=88N

m=?

We know Fc=mv^2/r

so 88=m(2.5)^2/2.1

88=6.25m/2.1

88=2.97m

m=88/2.97=29.63kg

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.