Answer:
speed and time are Vf = 4.43 m/s and t = 0.45 s
Explanation:
This is a problem of free fall, we have the equations of kinematics
Vf² = Vo² + 2g x
As the object is released the initial velocity is zero, let's look at the final velocity with the equation
Vf = √( 2 g X)
Vf = √(2 9.8 1)
Vf = 4.43 m/s
This is the speed with which it reaches the ground
Having the final speed we can find the time
Vf = Vo + g t
t = Vf / g
t = 4.43 / 9.8
t = 0.45 s
This is the time of fall of the body to touch the ground
Answer:
Mass of the sled in the snow 83.33 kg.
<u>Explanation</u>:
Given that,
Force applied to move the sled in the snow (F) = 75N
We know that
Newton's second law of motion is
F = ma (Or "force" is equal to "mass" times "acceleration".)
So if we move this around we can isolate mass and get mass
M = 83.33 kg
Mass of the sled in the snow <u>83.33 kg.</u>
Answer:
Dark matter does not affect our view, humans can see through them.
Explanation:
They do not affect our view because we can see right through the (weakly interacting) dark matter, as they do not interact or interfere with electromagnetic force.
Dark matter are often invisible substances and are difficult to spot because they don't absorb or reflect light.
Answer:
20,000 Ns
Explanation:
mass of exhaust gases, m = 50 kg
velocity of exhaust gases, v = 400 m/s
The momentum of a body is defined as the measurement of motion of body. mathematically, it is defined as the product of mass off the body an its velocity.
change in momentum of rocket = final momentum - initial momentum
= m x v - 0
= 50 x 400
= 20,000 Ns
