C. A 1200kg car is going 15m/s
Answer:
The net change in the internal energy of the gas in the piston is -343J
Explanation:
Because heat and workdone are the only means of energy transfer between the system and the surrounding, change in internal energy is given by;
∆E = q + w
q = heat transfer
w = workdone
Because heat is lost by the system, the heat transfer is negative
q = -413J
Because work is done on the system, workdone is positive
w = +70J
∆E = -413J + 70J
∆E = -343J
(a) 
<u>Explanation:</u>
Given:
Moment of Inertia of m₁ about the axis, I₁ = m₁x²
Moment of Inertia of m₂ about the axis. I₂ = m₂ (L - x)²
Kinetic energy is rotational.
Total kinetic energy is 
Work done is change in kinetic energy.
To minimize E, differentiate wrt x and equate to zero.

Alternatively, work done is minimum when the axis passes through the center of mass.
Center of mass is at 
Heat stroke had occurred when your body can no longer regulate its temperature. hope it helps :)
Answer:
a) 6 m/s
b) 14 m/s
Explanation:
Acceleration is change in velocity over change in time.
a) a = Δv / Δt
2 m/s² = (v − 4 m/s) / 1 s
v = 6 m/s
b) a = Δv / Δt
2 m/s² = (v − 4 m/s) / 5 s
v = 14 m/s