Answer:
The initial velocity of the ball is <u>39.2 m/s in the upward direction.</u>
Explanation:
Given:
Upward direction is positive. So, downward direction is negative.
Tota time the ball remains in air (t) = 8.0 s
Net displacement of the ball (S) = Final position - Initial position = 0 m
Acceleration of the ball is due to gravity. So,
(Acting down)
Now, let the initial velocity be 'u' m/s.
From Newton's equation of motion, we have:

Plug in the given values and solve for 'u'. This gives,

Therefore, the initial velocity of the ball is 39.2 m/s in the upward direction.
Answer:
Total momentum, p = 21.24 kg-m/s
Explanation:
Given that,
Mass of first piece, 
Mass of the second piece, 
Speed of the first piece,
(along x axis)
Speed of the second piece,
(along y axis)
To find,
The total momentum of the two pieces.
Solve,
The total momentum of two pieces is equal to the sum of momentum along x axis and along y axis.






The net momentum is given by :


p = 21.24 kg-m/s
Therefore, the total momentum of the two pieces is 21.24 kg-m/s.
Answer:
1 through 92 occur naturally on Earth
Answer:
friction force
Explanation:
force of friction is opposite to the force applied it resist the motion
Velocity = displacement / time
First, Always make sure that your units for things are the same. In this question, we are given time in seconds and hours. So, we need to make them all use 1 unit.
I will do seconds.
To convert 80km/h to m/s, divide by 3.6.
22.2222…. m/s = displacement / 2.1s
Multiply by 2.1s on both sides
46.6666……m = displacement
You travelled 47 meters.