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A block of mass √2kg is released from the top of an inclined smooth surface.If the spring constant is 100N/m and block comes to rest after compressing the spring by 1m, then the distance travelled by block before it comes to rest is? |
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Answer» At the bottom of the incline: Energy lost by the block as the spring slows it to a stop (the block's kinetic energy at the bottom of the incline) = Energy gained by the spring = (1/2)(100N/m)(1m)^2 = 50J As the block slides down the incline: Energy at the top = Energy at the bottom Ki + Ui = Kf + Uf Ui = Kf mgh = 50 J where h is the height of the incline (the altitude) (√2kg)(9.81m/s2)(h) = 50J h = 50/(√2x9.81) m h = 50/13.87 m h = 3.6 m The incline is a right triangle with height h (the altitude) and hypotenuse d (the plane length). sin45o = h/d, then d = 5m. Hence, the distance travelled by block before it comes to rest is 5m. |
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