Answer:
The instantaneous speed of the object after the first five seconds is 12.5 m/s.
(C) is correct option.
Explanation:
Given that,
An object starts at rest. Its acceleration over 30 seconds.
We need to calculate the instantaneous speed of the object after the first five seconds
We know that,
Area under the acceleration -time graph gives speed.
According to figure,




Hence, The instantaneous speed of the object after the first five seconds is 12.5 m/s.
Answer:
I think its 12 cm itself. Because in the question it is said that the length is same in all temperature
<span>(1) </span>Through the Second
Law of motion, the equation for Force is:
F = m x a
Where
m is mass and a is acceleration (deceleration)
<span>(2) </span>Distance is
calculated through the equation,
D
= Vi^2 / 2a
Where
Vi is initial velocity
<span>(3) </span>Work is calculated
through the equation,
W = F x D
Substituting
the known values,
Part
A:
<span>(1) </span> F = (85
kg)(2 m/s^2) = 170 N
<span>(2) </span> D = (37
m/s)^2 / (2)(2 m/s^2) = 9.25 m
<span>(3) </span> W = (170
N)(9.25 m) = 1572.5 J
Part
B:
<span>(1) </span> F = (85 kg)(4
m/s^2) = 340 N
<span>(2) </span>D = (37 m/s)^2 /
(2)(4 m/s^2) = 4.625 m
<span>(3) </span><span> W = (340
N)(4.625 m) = 1572.5 J</span>