Answer:
When air resistance equals the weight of an object, the object has reached free fall.
Explanation:
- When an object has only force acting on it as gravity then, it experiences free fall.
- During free fall all the forces except gravity is balanced by one another.
- In the question, object's weight is balanced by air resistance so it is in the state of free fall.
- At the null point of free fall, object experiences weightlessness i.e. it feels like object is not attracted by any force.
Answer:
I think decreases inversely
Explanation:
the third
Answer: F = 102141N
Explanation: <em><u>Newton's 2nd Law</u></em> states that a force can change the motion of a body. The relation is given by
F = m.a
whose units are:
[F] = N
[m] = kg
[a] = m/s²
Jenny's car, at the moment of the break, had acceleration:
![a=\frac{\Delta v}{\Delta t}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7B%5CDelta%20v%7D%7B%5CDelta%20t%7D)
![a=\frac{11}{0.14}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7B11%7D%7B0.14%7D)
a = 78.57 m/s²
Then, Force is
F = 1300*78.57
F = 102141 N
<u>Jenny's car experienced a force of </u><u>magnitude 102141N.</u>
the answer is concave lens
Answer:
P = 1097 Watt
Explanation:
given,
length of stairs, L = 130 m
inclination with horizontal,θ = 30°
mass of the football player = 105 Kg
time = 61 s
we know,
![Power = \dfrac{work}{time}](https://tex.z-dn.net/?f=Power%20%3D%20%5Cdfrac%7Bwork%7D%7Btime%7D)
Work = change in Potential energy
h = L sin 30°
h = 130 x 0.5
h = 65 m
W = m g h
W = 105 x 9.8 x 65
W = 66885 J
now,
![P = \dfrac{66885}{61}](https://tex.z-dn.net/?f=P%20%3D%20%5Cdfrac%7B66885%7D%7B61%7D)
P = 1097 Watt
hence, the power output on the way is 1097 W