Answer:
The velocity of the first block is 1.15m/s while of the second block 2.56m/s.
Explanation:
Momentum is only conserved in an isolated system, and because this problem requires us to find the value of the two variables, we need two equations; therefore, to conserved momentum the energy must be released in to the system only after the collision has occurred.
Therefore, from conservation of momentum



and from conservation of energy



Thus, we have two equations and two unknowns


which has solutions
and

Since the blocks cannot pass through each other, the 0.5kg block cannot have
(moves to the left) while the 0.4 kg block has
(moves to the right); therefore, we take the first solution for the velocities:
.
Thus , the velocity of the first block is 1.15m/s while of the second block 2.56m/s.
The object A has the greater mass compared to object B.
<u>Explanation:
</u>
The weight of any object on any planet is the measurement of gravity’s influence acting on the mass of the object. So for Earth, the acceleration will be acting on the object A’s mass (m) in Earth leading to the weight of the object A as 750 N.
While the acceleration of Jupiter will be acting on the object B’s mass kept in Jupiter to attain the weight of 750 N. So, the mass of both the objects at their respective planet will vary depending on the acceleration of each planet. We can check this as below:

So,

Thus,

Similarly for object B,


Thus,

Thus, the mass of object A is greater than the mass of object B.
Answer:
V = 0.9 m/s
Explanation:
The parameters given are:
Initial velocity U = 6.4 m/s
Time t = 0.64s
Height h = 2.05 m
To find the final velocity, let us use third equation of motion
V^2 = U^2 - 2gH
Since the ball is going upward, g will be negative
Substitute all the parameters into the formula
V^2 = 6.4^2 - 2 × 9.8 × 2.05
V^2 = 40.96 - 40.18
V^2 = 0.78
V = sqrt( 0.78)
V = 0.883 m/ s
V = 0.9 m/ s approximately