Answer:
-4.0 N
Explanation:
Since the force of friction is the only force acting on the box, according to Newton's second law its magnitude must be equal to the product between mass (m) and acceleration (a):
(1)
We can find the mass of the box from its weight: in fact, since the weight is W = 50.0 N, its mass will be
And we can fidn the acceleration by using the formula:
where
v = 0 is the final velocity
u = 1.75 m/s is the initial velocity
t = 2.25 s is the time the box needs to stop
Substituting, we find
(the acceleration is negative since it is opposite to the motion, so it is a deceleration)
Therefore, substituting into eq.(1) we find the force of friction:
Where the negative sign means the direction of the force is opposite to the motion of the box.
Answer:
265 J
Explanation:
where KE is kinetic energy, PE is potential energy, m is the mass of an object, v is the speed, h is the height and g is acceleration due to gravity.
Substituting 19.7 Kg for mass, 0.934 for h, 2.93 for v and 9.81 for g then
Answer:
Explanation:
From, the given information: we are not given any value for the mass, the proportionality constant and the distance
Assuming that:
the mass = 5 kg and the proportionality constant = 50 kg
the distance of the mass above the ground x(t) = 1000 m
Let's recall that:
Similarly, The equation of mption:
replacing our assumed values:
where 
So, when the object hits the ground when x(t) = 1000
Then from above derived equation:
By diregarding 
1000 + 0.981 = 0.981 t
1000.981 = 0.981 t
t = 1000.981/0.981
t = 1020.36 sec
The ball should put 200 N of force towards the golfer.
Newton's Third Law is every action has an equal and opposite reaction.
It's the ball exerting 200 N of force towards the club as well, but the opposite reaction is that it flies away.
Answer:
A. 
B. rev=10.79rev
Explanation:
A.
500rpm
the time is about 2.60s knowing the acceleration is:
so:
B.
The CD stop so the final velocity is vf=0 so:
Total revolutions:
