Answer:
The initial vertical velocity is zero, u = 0 m/s
Explanation:
Given;
height of the table, h = 0.55 m
horizontal distance traveled by the tennis, x = 0.12 m
Apply the following kinematic equation;
h = ut + ¹/₂gt²
where;
u is the initial vertical velocity = 0, since the tennis ball rolled off the edge of a table.
h = ¹/₂gt²
The time to fall from the vertical height is given by;

The initial horizontal velocity of the tennis is given by;
x = vₓt
vₓ = x / t
vₓ = (0.12) / (0.335)
vₓ = 0.358 m/s
Therefore, the initial vertical velocity is zero, u = 0 m/s and initial horizontal velocity, vₓ is 0.358 m/s
Answer:
Only (I) is true
i) Mass is conserved during a chemical reaction.
Answer:
2.5 x 10^{5} J
Explanation:
weight = 5,000 N
coefficient of friction = 0.05
distance = 1000 m
how much work is done by the dogs pulling the sledge
work done = force x coefficient of friction x distance
work done = 5000 x 0.05 x 1000 = 2.5 x 10^{5} J
Answer:
P=9.58 W
Explanation:
According to Newton's second law, and assuming friction force as zero:

The acceleration is given by:

So the force exerted by the motor is:

The work done by the motor is given by:


And finally, the power is given by:
