Find the kinetic energy of a ball of mass 200 grams moving at a speed of 20 m/s.
1 answer:
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Answer:
d = 68.18 m
Explanation:
Given that,
Initial velocity, u = 15 m/s
Finally it comes to stop, v = 0
Acceleration, a = -1.65 m/s²
Time, t = 2.5 s
We need to find the distance covered by the hayride before coming to a stop. Let d is the distance covered. Using third equation of motion to find it :
So, the hayride will cover a distance of 68.18 m.
Answer:
Explanation:
When unpolarized light passes through the first polarizer, the intensity of the light is reduced by a factor 1/2, so
(1)
where I_0 is the intensity of the initial unpolarized light, while I_1 is the intensity of the polarized light coming out from the first filter. Light that comes out from the first polarizer is also polarized, in the same direction as the axis of the first polarizer.
When the (now polarized) light hits the second polarizer, whose axis of polarization is rotated by an angle with respect to the first one, the intensity of the light coming out is
(2)
If we combine (1) and (2) together,
(3)
We want the final intensity to be 1/10 the initial intensity, so
So we can rewrite (3) as
From which we find
Answer:
the required minimum magnitude of the force F is 21 N
Explanation:
Given the data in the question,
m = 5 kg
width = 60 cm
height = 80 cm
Let force is F represent in the image below,
so when the block about to rotate normal shifted to edge of cube
mg(w/2) = Fh
F = mg(w/2) / h
we know that g = 9.8 m/s²
we substitute
F = (5 × 9.8 ( 60/2)) / 70
F = (5 × 9.8 × 30 ) / 70
F = 1470 / 70
F = 21 N
Therefore, the required minimum magnitude of the force F is 21 N
