The law says things travel in a straight line at constant speed unless acted upon by a force. But friction is a force but it can't be seen easily other than its effect, which is to bring the object to rest in seeming violation of the 1st law.
Explanation:
A pilot flying a weight; it takes t = 3.4 s to hit the ground, during which it travels a horizontal distance d = 120 m
h = g/2*t^2
h= 4.903*3.4^2
h=56.701 m
V = d/t
V= 120/3.4
V=35.3 m/sec
Now the pilot does a run at the same height but twice the speed.
How much time (t1) does it take the weight to hit the ground?
t1 = t = 3.4 sec (depending just upon height)
Kinetic energy E = m * v^2
<span>Since the acceleration of both books will be -neglecting air resistance - the same, the kinetic energy will be directly proportional to the mass of the book.</span>
Explanation:
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