Answer:
option (c)
Explanation:
90% of the body is submerged in water.
Now it is immersed in an unknown liquid whose density is less than the density of water.
Buoyant force acting on the body depends on the volume immersed, density of liquid and gravity.
As the density of liquid is less than the density of water, so the buoyant force acting on the body by the unknown liquid is less than water. So it is submerged less than 90% in this liquid.
Answer:
25 m/s in the opposite direction with the ship recoil velocity.
Explanation:
Assume the ship recoil velocity and velocity of the cannon ball aligns. By the law of momentum conservation, the momentum is conserved before and after the shooting. Before the shooting, the total momentum is 0 due to system is at rest. Therefore, the total momentum after the shooting must also be 0:
where are masses of the ship and ball respectively. are the velocities of the ship and ball respectively, after the shooting.
So the cannon ball has a velocity of 25 m/s in the opposite direction with the ship recoil velocity.
Kinetic energy is defined as the energy of motion. On the other hand, potential energy is the energy of non-motion.
Hope that helped =)