Answer:
B) Force of gravity
Explanation:
As it is the force which acts downward on the body towards the ground, it is clearly the force gravity represented by the arrow at A.
Answer:
Distance = 16.9 m
Explanation:
We are given;
Power; P = 70 W
Intensity; I = 0.0195 W/m²
Now, for a spherical sound wave, the intensity in the radial direction is expressed as a function of distance r from the center of the sphere and is given by the expression;
I = Power/Unit area = P/(4πr²)
where;
P is the sound power
r is the distance.
Thus;
Making r the subject, we have;
r² = P/4πI
r = √(P/4πI)
r = √(70/(4π*0.0195))
r = √285.6627
r = 16.9 m
The ball should take twice as long to return to its original position as it took to reach its maximum height, so it should return to its original position at 
.
Given:
V1 = initial velocity = 24 m/s
a = acceleration = 2.0 m/s^2
s = time = 8 s
V2 = final velocity = ?
For linear-motion problems with those given terms, the following formula is used:
V2 = V1 + as
Substituting the given values:
V2 = 24 + 2(8)
V2 = 24 + 16
V2 = 40 m/s
Therefore the car will have a speed of 40 m/s as it leaves the tunnel.
Answer:
The average power provided by the tension in the cable pulling the lift is = 714 W
Explanation:
Given data
Mass = 71 kg
Change in height = 123 m
When the lift moves in upward direction then in that case kinetic energy is constant & only potential energy changes.
Change in potential energy Δ PE = m g ( 
)
Δ PE = 71 × 9.81 × 123
Δ PE = 85670.73 J
Time = 2 min = 120 sec
So average power is given by
Therefore the average power provided by the tension in the cable pulling the lift is = 714 W
