26. Work = Force * distance or height
Force = mass * acceleration due to gravity (m*g)
So, Work = m * g * h
Work = 5 * 10 * 8 g is always = 10 m/s²
Work = 400J - (A)
27. Calc. the potential energy of both objects I and II
P.E = m * g * h
P.E of object I = 4 * 10 * 3 since g = 10 m/s²
= 120
P.E of object II = 6 * 10 * 2
=120
So, the potential energy of both objects are equal - III - (C)
29. Average acceleration = Increase in velocity/Elapsed time
The increase in velocity is 42 m/s
The elapsed time is 7 seconds
Average acceleration = 42/7 = 6 m/s² - (C)
28. It stays constant - (C)
