Answer: Rolling Friction
Explanation:A rolling ball stops because the surface on which it rolls resists its motion. A rolling ball stops because of friction.
A, something to remember is that if the numbers are even the answer too will be even. Every time hope this helps :>
Answer:
Tension force does no work
78 m/s
55701 J
Explanation:
The work done by the tension force of the rope is the dot product of the tension force vector and the distance travel vector as he swings. However, as these 2 vectors are always perpendicular to each other, their dot product would be 0 (cos(90) = 0). So the work done by tension force is 0.
If we neglect air resistance, then only gravity does work on the swimmer. We can apply the following energy conservation equation to calculate the kinetic energy once we let go of the rope.
where m is the mass of the swimmer, g = 9.81 m/s2 is the gravitational constant, Δh = 415 - 105 = 310 m is the height difference as he swings from horizontal point to the let go point. v is the let go speed. We can divide both sides by m
If the swimmer actually end up with only 67.8 m/s, then the loss in kinetic energy is due to air resistance during the swinging process. We can also find this by calculating the difference between the kinetics energies
Answer: 10kg
Explanation:
Given that:
Kinetic energy of puppy = 245J
Velocity of puppy = 7 m/s
mass of puppy = ?
Recall that kinetic energy is the energy possessed by a moving body. It is measured in joules, and depends on the mass and velocity of the moving body
i.e K.E = 1/2 x mass x (velocity)^2
245J = 1/2 x mass x (7 m/s)^2
245 = 0.5 x mass x 49
245 = 24.5 x mass
Mass = 245/24.5
Mass = 10kg
Thus, the mass of the puppy is 10kg
Answer: I'm pretty sure that this one's just an opinion but I guess 3 meters so you have a chance to notice it and move or 1 meter so that it doesn't hit as hard when it lands.