1. A football player pushes a tackle dummy forwards at a constant 0.85m/s for 11m using 7150J of energy. The tackling dummy mass is 120kg.

a) find force the player exerts?
b) what is the frictional force the dummy exerts?
c) what work is done by the friction as the dummy is slid along the field for 11m?
d) Is mass necessary for this question? if not, what force question could be asked that would require the mass of the dummy?

2. A person pushes a hockey puck with their stick at an angle so the vertical force is 22N [down] and the horizontal force is 45N [forward]. Assume the ice is frictionless.
a) what is the actual force the hockey plaer transmits to the puck?
b) what is the work done by the person pushing the stick if they push the puck for 3.0s as it moves with a constant velocity of 22m/s [forward]

To solve these physics questions, we will be using a few basic equations related to work, force, and energy.

1. For the first question:
a) To find the force the football player exerts, we can use the equation:
Force = Energy / Distance
Force = 7150 J / 11 m
Force ≈ 650 N

b) The frictional force exerted by the dummy can be assumed to be equal and opposite to the force exerted by the player. So, the frictional force is also approximately 650 N.

c) The work done by friction can be calculated using the equation:
Work = Force * Distance
Work = 650 N * 11 m
Work ≈ 7150 J (which is the same as the energy used by the player)

d) In this case, the mass of the dummy is not necessary for the given questions. However, if we wanted to calculate the acceleration of the dummy or the net force acting on the dummy, then mass would be required.

2. For the second question:
a) To find the actual force transmitted to the hockey puck, we can use the Pythagorean theorem since the forces are at right angles:
Actual Force = √(Vertical Force^2 + Horizontal Force^2)
Actual Force = √(22 N^2 + 45 N^2)
Actual Force ≈ 50.4 N (rounded to one decimal place)

b) Since the velocity of the puck is constant, we know that no net work is done by external forces. Therefore, the work done by the person pushing the stick is zero.

Note: In the absence of external forces like friction, the work done is zero, which is consistent with the concept of work as the transfer of energy.