Answer:
Zero; no force is required to keep it going
Explanation:
Since the cannon ball is fired into frictionless space, there will be nothing to stop it, so it will keep going and going.
Answer:
42.0×10² second²
Explanation:
Here, time is given in milisecond
(64800 ms)²
= 4199040000 ms²
The SI unit is seconds
1 second = 1000 milisecond



42.0×10² second²
Answer:
9.6J+88.2J=97.8J
Explanation:
Here the velocity of the seagull is given,mass is given and its height.
We have to find its mechanical energy my friend.
Mechanical energy=kinetic energy + potential energy.
First we will find kinetic energy.
For calculating kinetic energy we need mass and velocity,which are given here.
So, Ek=

So by substituting the values we get 9.6J.
Now we find the potential energy which is mgh.
By substituting the values we get 88.2J.
Then we add both of those and get 97.8J
I hope this satisfies you and make sure you contact me if it doesn't
Answer: Use less water
only turn on lights when needed
electrical cars
less gas usage
Explanation:
consider the motion of the tennis ball in downward direction
Y = vertical displacement = 400 m
a = acceleration = acceleration due to gravity = 9.8 m/s²
v₀ = initial velocity of the ball at the top of building = 10 m/s
v = final velocity of the ball when it hits the ground = ?
using the kinematics equation
v² = v²₀ + 2 a Y
inserting the values
v² = 10² + 2 (9.8) (400)
v = 89.11 m/s