Answer:
The average net force on the truck is 375 Newtons.
Explanation:
Using Newton's 3rd equation of motion, we have :
×a×s
where, v = final velocity = 25 m/s
u = initial velocity = 20 m/s
a = acceleration
s = distance traveled = 300 m
Using these values in the above equation, we get acceleration = 0.375 m/
Using Newton's second law, we have:
F=m×a
where m = mass = 1000 kg
a= acceleration = 0.375 m/
Putting values we have F=375 N
The rock strike the water with the speed of 15.78 m/sec.
The speed by which rock hit the water is calculated by the formula
v=
v=
v=15.78 m/sec
Hence, the rock strike the water with the speed of 15.78 m/sec.
Answer:

Explanation:
The density of an object is given by

where
m is the mass of the object
V is its volume
In this problem,
m = 42 kg
V = 22 m^3
Substituting into the equation, we find the object's density:

Answer:
A)
B)
Explanation:
Given that
Force = F
Increase in Kinetic energy = 

we know that
Work done by all the forces =change in the kinetic energy
a)
Lets distance = d
We know work done by force F
W= F .d
F.d=ΔKE


b)
If the force become twice
F' = 2 F
F'.d=ΔKE'
2 F .d = ΔKE' ( F.d =Δ KE)
2ΔKE = ΔKE'

Therefore the final kinetic energy will become the twice if the force become twice.