Answer:
Since the distance between the pivot and its weight is zero, the moment of its weight about the pivot (= weight × 0) is zero. Hence, the weight of the ruler can be ignored.
Hope this helps:)
Ok, so you've got to figure out a force F and you have the speed in which the boxer punches on determinate time and the mass of the sheet of paper.
So based on the formula that says that the Force is equal to the mass multiplied by the acceleration => F=ma.
You look at it and see that you only have mass which is measured on KG so there is no problem.
then you have the acceleration which is measured on meters and is defined by: a = Δv/Δt
So now you can replace the velocity and the time you have there
⇒ a 25m/s / 0.05s
you have computing that ⇒ 50m because the seconds were cancelled out.
and then you plug the meters into the force equation.
F=(0.005kg)(50)
F=0.25N
so the boxer will have a force of 0.25 Newton's.
Yes there is.
Momentum of an object is (its mass) times (its speed) .
To solve this problem we will apply the concepts related to the conservation of momentum. That is, the final momentum must be the same final momentum. And in each state, the momentum will be the sum of the product between the mass and the velocity of each object, then
Here,
= Mass of each object
= Initial velocity of each object
= Final velocity of each object
When they position the final velocities of the bodies it is the same and the car is stationary then,
Rearranging to find the final velocity
The expression for the impulse received by the first car is
Replacing,
The negative sign show the opposite direction.
Wave speed = (wavelength) x (frequency)
= (1.5 m) x (500 / sec)
= 750 m/s .
