Playing catch involves the ball moving in one direction in the air when you exert force. When the ball is in air, there is a gravitational force and a little it of backward air resistance until the other person catches it.
Answer: The correct answer is "Number of rope segments supporting the load".
Explanation:
Mechanical advantage: It is defined as the ratio of the force produced by a machine to the force applied on the machine. The ideal mechanical advantage of a machines is mechanical advantage in the absence of friction.
The ideal mechanical advantage of a pulley system is equal to the number of rope segments which is supporting the load. More the rope segments, It is more helpful to do the lifting the work.
It means that less force is needed for this task to complete.
Therefore, the correct option is (C).
Answer:
Approximately (assuming that the projectile was launched at angle of above the horizon.)
Explanation:
Initial vertical component of velocity:
.
The question assumed that there is no drag on this projectile. Additionally, the altitude of this projectile just before landing is the same as the altitude at which this projectile was launched: .
Hence, the initial vertical velocity of this projectile would be the exact opposite of the vertical velocity of this projectile right before landing. Since the initial vertical velocity is (upwards,) the vertical velocity right before landing would be (downwards.) The change in vertical velocity is:
.
Since there is no drag on this projectile, the vertical acceleration of this projectile would be . In other words, .
Hence, the time it takes to achieve a (vertical) velocity change of would be:
.
Hence, this projectile would be in the air for approximately .
Answer:
c. 1600J
Explanation:
The loss in potential energy of the boy is given by:
where
m = 40 kg is the mass of the boy
g = 9.8 m/s^2 is the acceleration of gravity
is the total change in the height of the boy (4 metres + 2 cm due to the compression of the spring)
Substituting, we find
Answer:
dV/dt = 9 cubic inches per second
Explanation:
Let the height of the cylinder is h
Diameter of cylinder = height of the cylinder = h
Radius of cylinder, r = h/2
dh/dt = 3 inches /s
Volume of cylinder is given by
put r = h/2 so,
Differentiate both sides with respect to t.
Substitute the values, h = 2 inches, dh/dt = 3 inches / s
dV/dt = 9 cubic inches per second
Thus, the volume of cylinder increases by the rate of 9 cubic inches per second.