The work done on the bullet is force•distance. This is also equivalent to the energy it has leaving the muzzle (work energy theorem). This kinetic energy is (1/2)(0.006kg)(336m/s)^2=338.7J. Then 338.7J=F•0.83m
F=338.7/0.83=408N
Answer:
2.63m
Explanation:
In order to use this expression, we must calculate the values of Velocity (V0) and Velocity(Ve). The initial velocity has only a horizontal component V(0) = V(0x), the final velocity also has a horizontal component since the ball it's at a point of trajectory, V(e) = V(ef). No forces act in the horizontal direction so the momentum of the ball in this direction is conserved, hence, V(0) = V(e)
Therefore, h(e) = h(0) = 2.63m
Answer:
Option (a) is the correct answer
Explanation:
Option (a) smaller than P is the correct answer for the given question. This is because the pressure (P) at any depth 'd' from the top surface of the water with density (ρ) is given as:
P = ρ × g × d
where,
g is the acceleration due to the gravity
thus from the above equation it can be concluded that the pressure at any depth 'd' is directly proportional to the density of the water.
thus,
in the given case the density of the water is lower than that in the first case.
Hence, the option (a) is the correct answer
The difference in speed is due to the different densities of the two mediums.
In fact, the higher the density of the medium, the greater the speed of sound. Sound travels faster in liquids (e.g. water) than in gases (e.g. air) because liquids are more dense than gases. This is due to the fact that in liquids, molecules are closer to each other, and since sound is essemptially vibration of molecules, these vibrations are transmitted faster from molecule to molecule in a more dense medium (such as a liquid) rather than in a less dense medium (such as a gas)
Explanation:
When a bullet is fired from a rifle, the actual firing makes a distinctive sound, but people at a distance may hear a second because the bullet creates a shock wave , a little sonic boom( speed of this sonic boom is greater than the speed of sound). It is this sound only that is heard by the people at a distance from the gun.