Answer:
F=50kg
D=5m
W=FD
therefore work done is 250Nm
Answer:
13.5 J
Explanation:
mass of ball, m = 3 kg
maximum height, h = 2.8 m
initial speed, u = 8 m/ s
Angle of projection, θ
use the formula of maximum height
Sin θ = 0.926
θ = 67.8°
The velocity at maximum height is u Cosθ = 8 Cos 67.8 = 3 m/s
So, kinetic energy at maximum height
K = 0.5 x 3 x 3 x 3
K = 13.5 J
Find the velocity of the object after one second.
v = vo + at
v = (0 m/s) + (9.8 m/s^2)(1 s)
v = 9.8 m/s
Now, using that, you can find the displacement in that one second between 1 and 2.
d = vot + (1/2)at^2
d = (9.8 m/s)(1 s) + (1/2)(9.8 m/s^2)(1 s)^2
d = 14.7 m
In order to compute the final velocity of the trains, we may apply the principle of conservation of momentum which is:
initial momentum = final momentum
m₁v₁ = m₂v₂
The final mass of the trains will be:
10,000 + 10,000 = 20,000 kg
Substituting the values into the equation:
10,000 * 3 = 20,000 * v
v = 1.5 m/s
The final velocity of the trains will be 1.5 m/s
