Answer:
7560 Joules
Explanation:
= Mass of first car = 
= Mass of second car = 
= Initial Velocity of first car = 0.3 m/s
= Initial Velocity of second car = -0.12 m/s
v = Velocity of combined mass
As linear momentum of the system is conserved

Energy lost is

The Energy lost in the collision is 7560 Joules
With that information you can only suppose a uniformly accelerated motion. This is, acceleration is constant.
Then, acceleration = change in velocity / change in time = (58 -54)km/h / 2 h = 4km/h / 2 h = 2 km/h^2
Then the equation for velocity, V is
V = Vo + a*t = Vo + 2 (km/h^2) * t = Vo + 2t
Vo is the initial velocity, which you can find using V = 54km/h and t = -2
Vo = V after 2 hours - a*(2hours) = 54km/h - 2(km/h^2)*2h = 54km/k - 4km/h = 50km/h
Then, the equation is: V = 50 km/h + 2t
Valid for constant acceleration.
Answer:
(i) W = 8.918 N
(ii) 
(iii) d = 9.1 cm
Explanation:
Part a)
As we know that weight of cube is given as


here we know that



now the mass of the ice cube is given as

now weight is given as

Part b)
Weight of the liquid displaced must be equal to weight of the ice cube
Because as we know that force of buoyancy = weight of the of the liquid displaced

So here volume displaced is given as



Part c)
Let the cube is submerged by distance "d" inside water
So here displaced water weight is given as



so it is submerged by d = 9.1 cm inside water