The answer for 1. Is false and the answer for 2. Is true
Gravity is the force that pulls us to the surface of the Earth, keeps the planets in orbit around the Sun and causes the formation of planets, stars and galaxies.
Answer:
Explanation:
From the question we are told that
The moment of inertia is
The final angular speed is
The time taken is
The initial angular speed is
Generally the average angular acceleration is mathematically represented as
=>
=>
Generally the torque is mathematically represented as
=>
=>
Answer:
Average speed of the car = 16.53 m.s
Explanation:
For first 5 seconds:
As the car starts from rest, so the initial speed of the car, u=0
Acceleration, a= 4 m/s^2
So, the final speed (speed at time, t=5 second)
v=u+at
v=0 + 4 x 5 = 20 m/s
Distance covered,
s=50 m
As the car maintained the constant speed of 20 m/s for the next 10 seconds.
Distance traveled in 10 seconds, d=20 x 10 =200 m
For the last 4 seconds:
The car slows down at the rate of 2.0 m / s ^ 2 from the speed of 20 m/s.
As the car slows down, so the acceleration will be negative, i.e a=-2 m/s^2
s=80-16=64 m.
Considering all three cases, the total distance covered=
=50+200+64=314 m
Total time= 5+10+4=19 s
So, the averate peed= Totat distance covered / total time taken
=314/19=16.53 m/s
Answer:
The net force acting on the tennis ball while it is in contact with the racquet is 50.73 N
Explanation:
The impulse-momentum theorem said that the net impulse is equal to the change of the momentum, this is:
but the net impulse is too the net force times the change in time:
so using (2) on (1) we have:
Decomposing that on x and y components:
(See figure below) with Pfx = m*vfx= m*vf*cos(15°)=(0.058kg)(40m/s)cos(15°),
Pox = -m*vox= m*vo*cos(15°)=-(0.058kg)(30m/s)cos(15°), the same analysis to Pfy and Poy gives
Pfy=(0.058kg)(40m/s)sin(15°), Poy=-(0.058kg)(30m/s)sin(15°), using those values on (3) and (4) and solving for Fy and Fx:
So the net force acting on the tennis ball while it is in contact with the racquet is: