Answer:
11.0 kg m/s
Explanation:
The impulse exerted on the cart is equal to its change in momentum:
where
m = 5.0 kg is the mass of the cart
is its change in speed
Substituting numbers into the equation, we find
Answer:
The answer is a wedge.
Explanation:
The wedge is a combination of two inclined planes. It is used to separate bodies which are held together by large forces, e.g, splitting timber
M.A.= slant height of wedge/thickness of wedge.
Hence a long thin wedge has a higher mechanical advantage than a short thick one; or the smaller the angle theta between the slant heights, the greater the mechanical advantage.
Answer:
A. Using artificial fertilizers instead of composting
Explanation:
Composting is actually more better than fertilizers usually, as it takes natural waste and with help of nature, returning the nutrients into soil once again. However, Artificial fertilizers usually uses chemicals to ensure that weed does not grow, and may contain other "unnatural" ingredients to ensure that only the crop grows on the field. Because of the usage of non-natural ingredients, any run-off can prove to be detrimental to any animals that eat any of the run-off infected material, or drink the polluted water.
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You can do this two ways:
1). Whatever kinetic energy the rolling ball has is the amount
of energy you have to absorb in order to stop it.
2). Whatever momentum the rolling ball has is the amount of
momentum you have to provide in the other direction to cancel it.
Since you asked about force and time, we sense 'impulse' in the
air, and we know that impulse is exactly a change in momentum.
So let's use #2 and talk about momentum and impulse.
Impulse = (force) x (time)
Momentum of a moving object is (mass) x (speed) .
-- Momentum of the first ball: (8 kg) x (0.2 m/s) = 1.6 kg-m/s
Impulse required to stop it = 1.6 kg-m/s
(force) x (10 sec) = 1.6
Force required = 1.6 / 10 = 0.16 Newton .
-- Momentum of the second ball: (4 kg) x (1 m/s) = 4 kg-m/s
Impulse required to stop it = 4 kg-m/s
(force) x (10 sec) = 4
Force required = 4 / 10 = 0.4 Newton .
You need more force o stop the second ball. Although its mass
is only 1/2 the mass of the 8kg ball, it's moving 5 times as fast,
and has 2.5 times the momentum of the bigger ball.
So you need 2.5 times as much impulse to stop it.
If you're going to push on each ball for the same length of time,
then you need to push 2.5 times as hard on the smaller ball in
order to stop it.
