When a cannon fires a cannonball, the cannon will recoil backward because the
a) energy of the cannonball and the cannon is conserved
b) momentum of the cannonball and cannon is conserved
c)energy of the cannon is greater than the energy of the cannonball
d) momentum of the cannon is greater than the energy of the cannonball
wouldn't the correct answer be d)?
No, the correct answer is b) momentum of the cannonball and cannon is conserved. When a cannon fires a cannonball, according to the law of conservation of momentum, the total momentum before and after the event must be the same. Since the cannonball gains momentum in one direction, the cannon itself must gain momentum in the opposite direction, causing it to recoil backward. The recoil is a result of the conservation of momentum, not the energy.
No, the correct answer is actually b) momentum of the cannonball and cannon is conserved.
To understand why, let's look at the concept of momentum. Momentum is defined as the product of an object's mass and velocity. In the case of the cannon firing a cannonball, both the cannon and the cannonball have momentum before the firing. According to the law of conservation of momentum, the total momentum of an isolated system remains constant if no external forces act on it.
When the cannon fires the cannonball, the cannonball gains momentum in the forward direction due to the force exerted on it by the combustion of gunpowder. However, since no external forces act on the system, the total momentum before and after the firing must be the same.
To conserve momentum, the cannon must also gain an equal amount of momentum in the opposite direction (backward). This backward momentum is what causes the cannon to recoil. So, the recoil of the cannon is a direct result of the conservation of momentum.
It's worth noting that this conservation occurs regardless of the relative masses of the cannon and the cannonball. The recoil of the cannon is determined by the conservation of momentum, not by comparing the energies of the cannon and the cannonball.