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# Momentum watch

1. HELPPP ASAPPP

When the ball is colliding with the ground There are 3 forces acting on the ball.
Normal force
Gravity
The force with which it collides ( there will be some extra force obviously)

They are asking the force the ground exerts on the ball means they are asking the contact force.

Now for the contact force if we resolve forces on the ball Contact force= weight + the additional force

I dont understand why are we using F=maThey are not asking the resultant force on the ball.

2. (Original post by Insia786)
HELPPP ASAPPP

When the ball is colliding with the ground There are 3 forces acting on the ball.
Normal force
Gravity
The force with which it collides ( there will be some extra force obviously)

They are asking the force the ground exerts on the ball means they are asking the contact force.

Now for the contact force if we resolve forces on the ball Contact force= weight + the additional force

I dont understand why are we using F=maThey are not asking the resultant force on the ball.

They're asking you to exclude weight so F=MA using the mass and acceleration of the ball gives an appropriate answer.
3. F = ma gives the resultant. Resultant obviously includes the weight
4. (Original post by Insia786)
F = ma gives the resultant. Resultant obviously includes the weight
The question asks you to ignore the weight
it wants you to ignore the weight and the component of reaction due to weight and just give the force needed to change the velocity of the ball
5. What would have been the force is weight wasnt ignored?
Im getting F from F=ma
2N
Now if we dont ignore weight whats the force
6. (Original post by Insia786)
HELPPP ASAPPP

When the ball is colliding with the ground There are 3 forces acting on the ball.
Normal force
Gravity
The force with which it collides ( there will be some extra force obviously)

They are asking the force the ground exerts on the ball means they are asking the contact force.

Now for the contact force if we resolve forces on the ball Contact force= weight + the additional force

I dont understand why are we using F=maThey are not asking the resultant force on the ball.

hmm....

good point why are you using

surely you'd use ?????

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