The mass of the boy and skateboard is there to throw you off. X and Y velocities are independent of each other, meaning that the only things you need are the velocity of the skateboard and the velocity of the boy. The total velocity of the boy is 7.5 m/s because the boy would still be moving with the 5 m/s that the skateboard has if the boy were to just jump straight up. Since the boy jumps forward with a velocity of 2.5 m/s, you would add them together.
Answer:
The speed is maximum and the acceleration is zero
Explanation:
- The speed of the mass in simple harmonic motion can be found by using the law of conservation of energy. In fact, the total mechanical energy of the mass-spring system is sum of kinetic energy and elastic potential energy:
where
m is the mass
v is the speed
k is the spring constant
x is the displacement
As we can see, when the displacement is zero (x=0), the term representing the kinetic energy is maximum, so v (the speed) is also maximum.
- The acceleration of the mass in simple harmonic motion is proportional to the restoring force acting on the mass, which is given by Hook's law
where
k is the spring constant
x is the displacement
When x = 0, F = 0, so the net force acting on the mass is zero. Therefore, this also means that the acceleration of the mass is also zero: a = 0.
Answer: 4.24m/s²
Explanation:
Acceleration is defined as change in velocity of an object with respect to time. Mathematically,
Acceleration (a) = Change in velocity/time taken
Acceleration (a) = final velocity (v) - initial velocity (u)/time taken (t)
Final velocity = 700m/s
Initial velocity = 0m/s (object beginning from rest)
Time taken = 2.75mins = (2.75 × 60)secs = 165seconds
Substituting the values in the acceleration formula a = v-u/t
a = 700-0/165
a = 4.24m/s²
<u>Given</u><u> </u><u>:</u><u>-</u>
- Mass of the object is 3kg .
- Its momentum is 1500kg m/s
<u>To </u><u>Find</u><u> </u><u>:</u><u>-</u>
<u>Solution</u><u> </u><u>:</u><u>-</u>
As we know that , the amount of motion contained in a body is called momentum . Mathematically ,
Answer:its B for the first one and the second one is D