For the dry ball it would be 200N = (2.0 Kg) (a) a = 100 m/s/s
For the wet ball it would be 200N = (2.1 Kg) (a) a = 95.23m/s/s (a lower accel.)
2. 1st law - Bob is a an object in motion and tends to stay in that motion unless there is a force (for example a seatbelt or Bob holding on). In this case Jim and the go-cart went left, but Bob continued going straight, and thus fell out.
3. 1st law - Like #2, Fred is in motion and continues in motion even if his bike stops.
4. 3rd law -When Sally kicks the bowling ball, she applies a force to the ball (action force). At the same time the bowling ball applies an equal force, in the opposite direction, to Sally's foot (reaction force). It is actually the ball hitting Sally that makes her toe hurt!
5. 1st law - An egg at rest will stay at rest until a force moves it.
6. 2nd law - Similar to #1, as the mass of the wagon goes up the acceleration has to go down.
7. 2nd law - By decreasing the mass of their bowling balls, Sally and Hayden can apply more acceleration to the ball. Remember Force = mass x acceleration.
8. 3rd law - Gravity pulls the bookbag down (action force) but the bookbag also pulls up on the Earth with an equal force (action force). We only notice the bookbag moving because Earth has so much more inertia than a bookbag. The bookbag moves a noticable distance while the Earth moves an unmeasurable tiny distance.
9. 2nd law - (Just like #7) If the mass is decreased, and his legs have the same force as before the disease, his acceleration will go up.
10. 3rd law - The horse is the action force and the wagon is the reaction force. Are you wondering how the wagon ever moves if the forces are balanced? To move the wagon, the horse must overcome the force of friction between the ground and the wheels, NOT the force of the wagon pulling on the horse.
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