A 2kg trolley runs down an inclined runway with a constant speed when given a sharp push.
(a) If the runway has a slope of 10 degrees, what is the frictional force acting on the trolley ?
(b) If the runway is now set at 30 degrees, what will be the acceleration of the trolley when it moves down the runway ?
Physics about resultant force
2009-04-14 3:41 am
回答 (1)
2009-04-14 4:00 am
✔ 最佳答案
a.When the runway has an inclination of 10*, it is friction-compensated.That is, the component of weight of the trolley parallel to the planebalances the frictional force.So, frictional force, f
= mgsin10*
= (2)(10)sin10*
= 3.47 N
b. By Newton's 2nd law of motion,
mgsin30* - f = ma
(2)(10)sin30* - 3.47 = 2a
Acceleration, a = 3.26 ms-2
參考: Physics king
收錄日期: 2021-04-19 14:07:16
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