William Gilbert is known as the father of electricity.
Answer:
I hope the picture below help.
Explanation:
Answer:
number 4
Explanation:
The reflection of light happens when the light bounces off the reflecting surface. That is described by the last (bottom) schematics.
Therefore, select answer number 4.
The car's speed was zero at the beginning of the 12 seconds,
and 18 m/s at the end of it. Since the acceleration was 'uniform'
during that time, the car's average speed was (1/2)(0 + 18) = 9 m/s.
12 seconds at an average speed of 9 m/s ==> (12 x 9) = 108 meters .
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That's the way I like to brain it out. If you prefer to use the formula,
the first problem you run into is: You need to remember the formula !
The formula is D = 1/2 a T²
Distance = (1/2 acceleration) x (time in seconds)²
Acceleration = (change in speed) / (time for the change)
= (18 m/s) / (12 sec)
= 1.5 m/s² .
Distance = (1/2 x 1.5 m/s²) x (12 sec)²
= (0.75 m/s²) x (144 sec²) = 108 meters .
Answer:
19.53 cm
Explanation:
The computation of the height is as follows:
Here we applied the conservation of the energy formula
As we know that
P.E of the block = P.E of the spring
m g h = ( 1 ÷ 2) k x^2
where
m = 0.15
g = 9.81
k = 420
x = 0.037
So now put the values to the above formula
(0.15) (9.81) (h) = 1 ÷2 × 420 × (0.037)^2
1.4715 (h) = 0.28749
h = 0.19537 m
= 19.53 cm