If we consider any system moving with u<span>niform circular motion we can notice that the MAGNITUDE of the accelaration remains constant. However, there is a change in the direction of the acceleration at every instant of time .
As the object moves through the circle the acceleration changes its direction always pointing to the center of the circle.</span>
Answer:
Approximately
, assuming friction between the vehicle and the ground is negligible.
Explanation:
Let
denote the mass of the vehicle. Let
denote the initial velocity of the vehicle. Let
denote the spring constant (needs to be found.) Let
denote the maximum displacement of the spring.
Convert velocity of the vehicle to standard units (meters per second):
.
Initial kinetic energy (
) of the vehicle:
.
When the vehicle is brought to a rest, the elastic potential energy (
) stored in the spring would be:
.
By the conservation of energy, if the friction between the vehicle and the ground is negligible, the initial
of the vehicle should be equal to the
of the vehicle. In other words:
.
Rearrange this equation to find an expression for
, the spring constant:
.
Substitute in the given values
,
, and
:

Answer: The correct option is A.
Explanation:
Inertia is a state of an object or body to maintain its state. It resists any change in its state.
Newton's first law of inertia: When an objects is in state of motion, it will remain its state of motion or if it is in state of rest then it will remain in rest unless it is acted upon by external motion.
In the given options, a ball sits motionless on the ground is good example of Newton's first law motion. No external force is acting in this case.
In options (B), (C) and (D) , the external force is acting.
Therefore, the correct option is A.
Answer:
a fad diet is basically a diet that was a trend or that was popular for a short amount of time and makes unreasonable claims for fast and very much wanted results
Explanation:
Average speed = (distance covered) / (time to cover the distance)
Average speed = (4 meters) / (5 seconds)
Average speed = (4/5) (meters/seconds)
Average speed = 0.8 m/s