imagine a flat, lightweight wheeled cart that's low to the ground and has well-oiled bearings. what would happen if you approached the cart, stepped onto it, and walked along its length at a constant speed? it would
a) remain nearly stationary
b) advance along with you
c) move rapidly in the opposite direction
d) move forward then backward
e) none of the above
what do you think? Consider Newtons laws of motion.
would it be c?
To determine what would happen when you approach the cart, step onto it, and walk along its length at a constant speed, we can consider the principle of conservation of momentum.
The cart is initially at rest, which means the momentum of the cart and your combined system is zero. When you step onto the cart, your body gains momentum in the forward direction due to your walking. According to the conservation of momentum, the combined momentum of the cart and your body should remain zero.
Now, let's analyze the provided options:
a) Remain nearly stationary: If the cart were to remain nearly stationary, it would mean that there is no change in momentum. However, by stepping onto the cart and walking, you are transferring momentum to the system. Therefore, this option is not correct.
b) Advance along with you: As mentioned earlier, your walking transfers momentum to the system. According to the conservation of momentum, the cart would move forward to balance the momentum gained by your body. Hence, this option is correct.
c) Move rapidly in the opposite direction: This option implies that the cart would move in the opposite direction to your walking. However, this contradicts the conservation of momentum, as it would result in non-zero total momentum. Therefore, this option is not correct.
d) Move forward then backward: This option suggests that the cart would move forward initially and then move backward. Again, this violates the conservation of momentum, as it would lead to non-zero momentum. Thus, this option is not correct.
e) None of the above: Based on the explanations above, option (b) - Advance along with you - is correct.
Therefore, when you approach the cart, step onto it, and walk along its length at a constant speed, the cart would advance along with you.