Answer:
Option 5. 1 and 3
Solution:
The only forces acting on the tennis ball after it has left contact with the racquet and the instant before it touches the ground are the force of gravity in the downward direction and the force by the air exerted on the ball.
The ball after it left follows the path of trajectory and as it moves forward in the horizontal direction the force of the air acts on it.
In the whole projectile motion of the ball, the acceleration due to gravity acts on the ball thus the force of gravity acts on the ball in the downward direction before it hits the ground.
The force of gravity F_g will act downwards.
Normal force F_N will act upwards equal to the force of gravity.
A force due to uniform acceleration F_a will act upwards to move the elevator upwards.
Thus, figure E is the correct answer.
Answer:
B
Explanation:
Nuclear fission is the process of splitting apart nuclei. When nuclei fission energy is released. So much energy is released that there is a measurable decrease in mass, from the mass-energy equivalence. This means that some of the mass is converted to energy.
The law of reflection states that the angle of incidence and the angle of reflection will always be equal.
When a ray of light reflects off a surface, the angle of reflection is equal to the angle of incidence.
Answer:
20 seconds
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
r = Radius of robot = 0.5 m
= Angular acceleration = 2 rad/s²
Linear acceleration is given by
While speeding up time taken is 10 seconds
The time taken to slow down is 10 seconds
Total time the trial is rum is 10+10 = 20 seconds
