Answer:
KE= 1/2 * mass * Velocity^2
Explanation:
1/2 * 72.0kg* 79^2 m/s = 224676 J
Answer:
(a) 86.65 J
(b) 149.65 J
Solution:
As per the question:
Diameter of the pool, d = 12 m
⇒ Radius of the pool, r = 6 m
Height of the pool, H = 3 m
Depth of the pool, D = 2.5 m
Density of water,
Acceleration due to gravity, g =
Now,
(a) Work done in pumping all the water:
Average height of the pool, h =
h =
Volume of water in the pool, V =
Mass of water,
Work done is given by the potential energy of the water as:
(b) Work done to pump all the water through an outlet of 2 m:
Now,
Height, h = 2.75 + 2 = 4.75
Work done,
Answer:
a principle stating that energy cannot be created or destroyed, but can be altered from one form to another.
Explanation:
Answer:
D. The motion cannot be determined without knowing the speeds of the objects before the collision.
Explanation:
This question is tricky! We know the object moving to the left has a greater mass than the one moving to the right. We'd <em>assume</em> they would move to the left because the leftwards object has a greater mass, right?
Not. So. Fast.
We can solve for the objects' final velocity using the formula for momentum, m₁v₁ + m₂v₂ = (m₁ + m₂)v .
Now here's where the trap is sprung: <em>we don't think about the equation</em>. This shows that the final velocity of the objects and the direction depends on both the mass of the objects <em>and</em> their initial velocity.
Basically, what if the 3 kg object is moving at 1 m/s and the 4 kg object is moving at –0.5 m/s? The objects would move to the <em>right</em> after the collision!
Do we know the velocity of these objects? No, right?
That means we <em>can't</em> determine the direction of their motion <u>unless we know their initial, pre-collision velocity</u>. This question is tricky because we look at the 4 kg vs. 3 kg and automatically assume the 4 kg object would dictate the direction of motion. That's not true. It depends on velocity as well.
I hope this helps you! Have a great day!
That would be called VOLT