Answer:
(A) V = 9.89m/s
(B) U = -2.50m/s
(C) ΔK.E = –377047J
(D) ΔK.E = –257750J
Explanation:
The full solution can be found in the attachment below. The east has been chosen as the direction for positivity.
This problem involves the principle of momentum conservation. This principle states that the total momentum before collision is equal to the total momentum after collision. This problem is an inelastic kind of collision for which the momentum is conserved but the kinetic energy is not. The kinetic energy after collision is always lesser than that before collision. The balance is converted into heat by friction, and also sound energy.
See attachment below for full solution.
What's the weight of the pear ?
Weight = (mass) x (gravity) = (1 kg) x (9.8 m/s²) = 9.8 Newtons.
OK. We know there's a force of 9.8 Newtons acting downwards on the pear.
Is the pear accelerating ? No ! It's just laying there on the table.
If it's not accelerating, then we know that the net force on it must be zero.
So there must be ANOTHER force acting UPWARDS on it, to exactly
cancel out the downward force of its weight. THAT's the "normal" force ...
the upward force that the table exerts on the pear. It must also be 9.8N,
but UPwards, so that if you add it to the weight, the sum is zero.
The answer is D light rays shine on an object which then reflects back to our retina
Answer:
a)
85.05 N/m
b)
179.81 rad/s
Explanation:
a)
k = spring constant of the spring
m = mass of the block = 0.473 kg
x = stretch caused in the spring = 0.109 m
h = height dropped by the block = 0.109 m
Using conservation of energy
Spring potential energy gained by the spring = Potential energy lost by the block
(0.5) k x² = mgh
(0.5) k x² = mgx
(0.5) k x = mg
(0.5) k (0.109) = (0.473) (9.8)
k = 85.05 N/m
b)
angular frequency is given as
= 179.81 rad/s
Below are the choices that can be found in the other sources:
A. diffraction
<span>B. refraction </span>
<span>C. reflection </span>
<span>D. transmission
</span>
The answer is diffraction. It means that <span>the process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced.</span>