Answer B is the correct answer
We know that kinetic energy , where m is the mass of object and v is the velocity of object.
In this case only velocity is the variable, mass remains constant.
So point having higher velocity has higher kinetic energy.
When it leaves the racket, the ball will be having a certain height, but just before it reaches the ground it will not having any height. So maximum velocity of ball is at that time when it reaches just above the ground.
So option B is the correct answer.
Answer:
Fr = 48 [N] forward.
Explanation:
Suppose the movement is on the X axis, in this way we have the force of the engine that produces the movement to the right, while the force produced by the brake causes the vehicle to decrease its speed in this way the sign must be negative.
∑F = Fr
The movement remains forward, since the force produced by the movement is greater than the braking force.
Answer:
7.9 x 10^21 pound-force
Explanation:
The average distance between the Earth and sun is 150 trillion meters, or 1.5 x 10^11 meters. The mass of the sun is 1.99 x 10^30 kilograms, while the Earth weighs in at 6.0 x 10^24 kilograms. The gravitational constant is 6.67 x 10^-11 meter^3 / (kilogram - second^2). So the Earth and sun pull on each other with a force equal to 3.52 x 10^22 newtons. The newton is a unit of force equal to a kilogram-meter/second^2. One newton is equal to 0.22 of the rarely used English unit called pound-force, so 3.52 x 10^22 newtons is 7.9 x 10^21 pound-force.
Answer:
explained
Explanation:
Electrons use light energy to move among energy levels within an atom because of the following reason
Electrons in each orbit around an atom have some specific energy. However, they can emit or absorb photons of the energy equal to difference of the energy between these specific energy levels within an atom. If the electron absorbs an photon, it can move up the energy level, if the electron emits a photon, it can move down to a energy level.
Let's call
the mass of the star and
the mass of the planet, which should cancel. The gravitational force should equal the centripetal force:
We compute
This is Keppler's Law. We convert to MKS as we plug in and get
kg
which is about two and a half solar masses if I haven't made any errors.