5. A 72 kg firefighter slides down a fire pole with a downward acceleration of 2.80 m/s2. What is the force of friction exerted by the pole on the firefighter?(You will need to find
the weight force acting on the object by knowing the mass.)
or

Explanation:

Without friction, the firefighter would accelerate downward at 9.81 m/s²

As he/she only accelerates at 2.80 m/s², this means the friction is causing an upward acceleration of 9.81 - 2.80 = 7.01 m/s²

Ff = ma

Ff = 72(7.01) = 504.72 = 505 N upward

d. platinum would have the greatest temperature increase because it has the lowest specific heat.