Answer:
Mass of the box = 0.9433 kg
Explanation:
Mass of racket-ball 
= 0.00427 kg
Velocity of racket-ball before collision 
= 22.3 m/s
Velocity of racket-ball after collision with box 
= -11.5 m/s
[Since ball is bouncing back, so velocity is taken negative.]
Velocity of the box before collision 
= 0 m/s
<em>[Since the box is stationary, so velocity is taken zero]</em>
Velocity of box moving forward after collision 
= 1.53 m/s
To find the mas of the box 
.
By law of conservation of momentum we have:
Momentum before collision = Momentum after collision
This can be written as:
We can plugin the given value to find
Adding both sides by 0.4911
Dividing both sides by 1.53.
∴ 
kg
Mass of the box = 0.9433 kg (Answer)
Answer:
B is the best answer for this question
F(g)= Gm1m2/ r^2
If mass is increased, so will the force of gravity because it is in direct relationship with the gravitational force, but if distance is increased, the force of gravity will decrease because it is indirectly related ( since it is on the bottom of the equation)
Answer:
The work done is 205 kJ.
Explanation:
Hi there!
Work can be calculated using the following equation:
W = F · Δx
Where:
W = work
F = applied force
Δx = displacement
In this case, the force varies with the position, so we can divide the traveled distance in very small parts and calculate the work done over each part of the trajectory. Then, we have to sum all the works and we will obtain the work done from the initial position (xi) to the final position (xf). This is the same as saying:
W = ∫ F · dx
F = 3.6 N/m³ · x³ - 76 N
W = ∫ (3.6 x³ - 76)dx
W = 0.9 x⁴ - 76x
Evaluating from xi to xf:
W = 0.9 N/m³ (21.9 m)⁴ - 76 N · 21.9 m - 0.9 N/m³(5.41 m)⁴ + 76 N · 5.41 m
W = 205 kJ
