When resistance force on a lever increases, nothing happens automatically.
But if you want to keep lifting the load, then YOU must increase the force of
your effort in order to make it happen.
Answer:
Petroleum is a nonrenewable resource. This being because it is a natural gas that take millions of years for it to reform which means each part of it is a once in a lifetime use.
<u>Answer:</u> The velocity of released alpha particle is 
<u>Explanation:</u>
According to law of conservation of momentum, momentum can neither be created nor be destroyed until and unless, an external force is applied.
For a system:

where,
= Initial mass and velocity
= Final mass and velocity
We are given:

Putting values in above equation, we get:

Hence, the velocity of released alpha particle is 
Explanation:
It is given that,
Initial speed of the broad jump, u = 12 m/s
It is launched at an angle of 20 degrees above the horizontal. Let t is the time for which the track star i in the air before returning to Earth. The motion of the track star in the broad jump can be treat as the projectile motion. The time of flight of the projectile is given by :

Putting all the values in above equation as :

t = 0.837 seconds
So, the time for which the track star is in air is 0.837 seconds. Hence, this is the required solution.
<u>Answer:</u>
For 1: The correct option is Option C.
For 3: The final velocity of the opponent is 1m/s
<u>Explanation: </u>
During collision, the energy and momentum remains conserved. The equation for the conservation of momentum follows:
...(1)
where,
are the mass, initial velocity and final velocity of first object
are the mass, initial velocity and final velocity of second object
<u>For 1:</u>
We are Given:

Putting values in equation 1, we get:

Hence, the correct answer is Option C.
Impulse is defined as the product of force applied on an object and time taken by the object.
Mathematically,

where,
F = force applied on the object
t = time taken
J = impulse on that object
Impulse depends only on the force and time taken by the object and not dependent on the surface which is stopping the object.
Hence, the impulse remains the same.
Let the speed in right direction be positive and left direction be negative.
We are Given:

Putting values in equation 1, we get:

Hence, the final velocity of the opponent is 1m/s and has moved backwards to its direction of the initial velocity.