Answer:
a) F = 527.65 N, Force applied is upwards.
b)F = - 527.65 N, where, negative sign depicts Force is applied downwards.
Explanation:
Data provided:
Weight of the firefighter = 756 N
Mass of the firefighter = 756/9.8 = 77.14 Kg
Acceleration, a = 2.96 m/s²
a) In the absence of the pole the firefighter would have been moving down with an acceleration of 9.8 m/s (i.e the acceleration due to the gravity), but due to the presence of the pole the acceleration of the firefighter has been reduced. thus, a force is applied by the pole on the firefighter to reduce the acceleration.
therefore, we have
F = ma(net) = 77.14 × (9.8-2.96) = 527.65 N, Force applied is upwards.
B) According to the Newton's third law, the force will be equal and opposite to the force in the part a)
thus, we have
F = - 527.65 N
Here we have perfectly inelastic collision. Perfectly inelastic collision is type of collision during which two objects collide, stay connected and momentum is conserved. Formula used for conservation of momentum is:

In case of perfectly inelastic collision v'1 and v'2 are same.
We are given information:
m₁=0.5kg
m₂=0.8kg
v₁=3m/s
v₂=2m/s
v'₁=v'₂=x
0.5*3 + 0.8*2 = 0.5*x + 0.8*x
1.5 + 1.6 = 1.3x
3.1 = 1.3x
x = 2.4 m/s
The thermal energy that is generated due to friction is 344J.
<h3>What is the thermal energy?</h3>
Now we know that the total mechanical energy in the system is constant. The loss in energy is given by the loss in energy.
Thus, the kinetic energy is given as;
KE = 0.5 * mv^2 =0.5 * 15.0-kg * (1.10 m/s)^2 = 9.1 J
PE = mgh = 15.0-kg * 9.8 m/s^2 * 2.40 m = 352.8 J
The thermal energy is; 352.8 J - 9.1 J = 344J
Learn more about thermal energy due to friction:brainly.com/question/7207509
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