Answer:
Work done,
Solution:
Consider the weight of water is
Let us assume:
r = 6 ft
R = 12 ft
h = 15 ft
Now, let us consider the volume of the cross-section (horizontal) be dV, from the rim top let y be its vertical distance and dw be its weight
Now,
radius =
radius =
radius =
dV =
The weight of cross-section is given by:
Now, the work done is given by:
On solving the above equation , we get:
Answer:
Work will be same on each case.
Explanation:
Work done = Energy change
The total work done by carrying two buckets in one trip or all in one trip is the same as the energy change in the six buckets is same in both cases. Either way buckets will gain the same increase in potential energy so work done is change.
But you will feel more exhausted when you carry all six once and will feel more comfortable when carrying 2 at a round.
This is not because you will doing different amount of work but due to drawing out same amount of work in different ranges of time.
When carrying 2 at a round you draw same amount of energy in lesser time so body can easily support the energy draining out than in the other case of carrying all 6 buckets once.
Answer:
254.75 m/s
Explanation:
The ball velocity just before it hits the ground would consists of 2 components:
- Horizontal velocity: ignore air resistance, would be the same as initial horizontal velocity, which is 250 m/s
- Vertical velocity: generated by gravitational acceleration g = 10m/s2 after falling for 120m
We can solve for vertical velocity first before it hits the ground using the following equation of motion:
where v0 = 0 m/s is the initial vertical velocity of the ball when it's fired, v is the final velocity of the ball when it hits the ground, a = 10 m/s2 is the gravitational acceleration of the ball, and is the distance traveled.
The magnitude of the velocity is the combination of both vertical and horizontal
A. The fly's velocity to the ground is less than the car's velocity to the ground.
Answer:
150 J
Explanation:
If there is not any dissipative force in the system, the mass and the spring will oscillate eternally., but of course, we assume this is a theoretical situation. The conservation of energy in a system implies that the sum of the potential energy plus kinetic energy remains constant, therefore if in the initial point the mass has 200 J (potential energy) and is at rest ( kinetic energy = 0) the overall energy at the beginning is 200 J. At any point of the oscillation if the potential energy is 50 J the kinetic energy must be 150 J.