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Explanation:
A wall that is acted upon by a force of 20N does not move suggests that no work has been done on the wall.
Work done is the force applied to move in the direction of the applied force.
Work done = force x distance.
Since the distance is 0, the work done on the body too is zero.
Work is only done when forces moves a body through a given distance.
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Given: distance 1 d₁ = 40 m; distance 2 d₂ = 3.8 m g = -9.8 m/s²
Initial Velocity Vi = 0 Final Velocity of stone 2 is unknown = ?
Total distance dₓ = d₁ - d₂ = 40 m - 3.8 m = 36.2 m
Formula: a = Vf² - Vi²/2d derive for Final Velocity Vf
acceleration is now due to gravity, therefore a = g
Vf = √2gd Vf = √2(9.8 m/s²)(36.2 m)
Vf = 26.64 m/s
Reason: The second stone will still start from rest.
You need to know the specific heat capacity of air.
Then energy needed = 0.005 x sp.heat.cap x 10