- #1
Clari
- 62
- 0
1. A ball is dropped from a height of 20m and rebounds with a velocity which is 3/4 of the velocity with which it hit the ground. What is the time interval between the first and second bounces?
I don't have any idea about dealing with this problem.
2.Explain why a projectile fired from a long-barrelled gun is subject to less acceleration than a projectile fired from a short-barrelled gun if the range is the same in both cases.
umm...I don't even know what is the difference between long-barrelled gun and short-barrelled gun.
3. A bird of mass 0.5kg hovers by beating its wing of effective area 0.3 m^2. Estimate the velocity imparted to the air, which has a densiy of 1.3 kgm^-3, by the beating of the wings.
again, I don't know how to do this question... >_<
I don't have any idea about dealing with this problem.
2.Explain why a projectile fired from a long-barrelled gun is subject to less acceleration than a projectile fired from a short-barrelled gun if the range is the same in both cases.
umm...I don't even know what is the difference between long-barrelled gun and short-barrelled gun.
3. A bird of mass 0.5kg hovers by beating its wing of effective area 0.3 m^2. Estimate the velocity imparted to the air, which has a densiy of 1.3 kgm^-3, by the beating of the wings.
again, I don't know how to do this question... >_<