A cart moving along a horizontal road at a speed of 36 km / h begins to climb the hill, the height of which is 4.2 m.
A cart moving along a horizontal road at a speed of 36 km / h begins to climb the hill, the height of which is 4.2 m. What speed will the cart have on the top of the hill? Resistance is neglected.
To find the speed of the used cart on the top of the hill, we use the equality: En1 + Ek1 = Ek0 and m * g * h + m * V1 ^ 2/2 = m * V02 / 2, whence we express: V1 = √ (2 * (V0 ^ 2 / 2 – g * h)).
Constants and variables: V0 – speed of the used bogie on a horizontal road (V0 = 36 km / h (10 m / s)); g – acceleration due to gravity (g ≈ 10 m / s2); h is the height of the slide (h = 4.2 m).
Calculation: V1 = √ (2 * (V0 ^ 2/2 – g * h)) = √ (2 * (10 ^ 2/2 – 10 * 4.2)) = 4 m / s.
Answer: At the top of the hill, the cart used should have a speed of 4 m / s.