Answer:
d = 39.7 km
Explanation:
initial position of the boat is 45 km away at an angle of 15 degree East of North
so we will have


after some time the final position of the boat is found at 30 km at 15 Degree North of East
so we have


now the displacement of the boat is given as



so the magnitude is given as


To solve this problem we will apply Newton's second law. The second law says that mass by acceleration is equivalent to the Force exerted on a body. Mathematically this

Here,
m = mass
a = Acceleration
The ball flies through the air under the effect of gravity only. Therefore the acceleration is due to gravity, we have that

Then,

Replacing


The negative sign implies that the force acting on the ball is in the downward direction that is towards the negative y direction.
3.5 Newton of force is needed to accelerate 140g of ball at 25 m/s^2 using the formula f=ma
Change 140g to kg
Answer:
4992 J
Explanation:
Force, F = 39 N
Distance, s = 128 m
Work done = force x distance
W = 39 x 128
W = 4992 J
Thus, the work done is 4992 J.