F = 2820.1 N
Explanation:
Let the (+)x-axis be up along the slope. The component of the weight of the crate along the slope is -mgsin15° (pointing down the slope). The force that keeps the crate from sliding is F. Therefore, we can write Newton's 2nd law along the x-axis as
Fnet = ma = 0 (a = 0 no sliding)
= F - mgsin15°
= 0
or
F = mgsin15°
= (120 kg)(9.8 m/s^2)sin15°
= 2820.1 N
Hi there!

To find the potential energy of the ball at B, we can use the equation:
PE = mgh
Plug the given gravity, mass, and height:
PE = (1.5)(0.5)(9.8) = 7.35 J
At A, all of this potential energy is changed to kinetic energy, so we can use the following equation:
v = √2KE/m
Plug in the solved for energy and mass:
v = √2(7.35)/1.5
Solve:
v ≈ 3.13 m/s
Answer:

Explanation:
Gravity on the surface of planet is given as

as we know that


now gravity on the planet is

so we have

now we know that

so we will say



Answer:
a. closer to 20∘C
Explanation:
= mass of pallet = 50 g = 0.050 kg
= specific heat of pallet = specific heat of iron
= Initial temperature of pellet = 200 C
= mass of water = 50 g = 0.050 kg
= specific heat of water
= Initial temperature of water = 20 C
= Final equilibrium temperature
Also given that
Using conservation of energy
Energy gained by water = Energy lost by pellet

hence the correct choice is
a. closer to 20∘C