Answer:
The new speed of the ball is 176.43 m/s
Explanation:
Given;
mass of the ball, m = 7 kg
initial speed of the ball, u = 5 m/s
applied force, F = 300 N
time of force action on the ball, t = 4 s
Apply Newton's second law of motion;

where;
v is new speed of the ball

Therefore, the new speed of the ball is 176.43 m/s
Answer:
B = 0.75 T
Explanation:
As we know that the force on a moving charge in magnetic field is given by the formula

here we have

here we know that



now from above equation we have


The temperature decreases as you go up.
Vector 1 has components


and vector 2 has


Add these vectors to get the resultant, which has components


The magnitude of the resultant is

with direction
such that

or about 50º N of E.
Answer:
The kinetic energy is 1200 J
Explanation:
The Principle of Conservation of energy states that "energy is neither created nor destroyed, it is transformed".
This means that energy can be transformed from one form to another, but the total amount of energy always remains constant, that is, the total energy is the same before and after each transformation.
The mechanical energy of a body or a physical system is the sum of its kinetic energy and the potential energy. According to the Principle of Conservation of Energy for mechanical energy, the total mechanical energy that a body possesses is constant at every instant of time.
Since mechanical energy is equal to the sum of kinetic energy and gravitational potential energy that a body possesses, the only way to stay constant is that:
- when the kinetic energy increases the gravitational potential energy decreases,
- when gravitational potential energy increases, kinetic energy decreases.
Due to the Principle of Conservation of Energy you can say that the gravitational potential energy is converted to kinetic energy. So Gravitational potential energy at the top = kinetic energy at the bottom
<u><em>The kinetic energy is 1200 J</em></u>