Power is the rate of work that is done per time. Work is calculated from the product of force and the displacement. So, by using the definition of power and work, we can relate power with force, displacement and the time. We do as follows:
Power = Work / time
Power = Force x displacement / time
Power = 21 N (9 m) / 3 s
Power = 63 J /s = 63 W
Answer:
T=+1.133N
Explanation:
Tension and weight are forces that have opposite directions
Weight is negative (downward)
W=m*g= 0.11kg*(-9.8m/s^2)
W= -1.078N
Tension is possitive (upward)
The total force will be the sum of both (the difference taking in consideration the direction)
Ft= T+W
Also the total force is the product of the mass due to acceleration:
Ft=m*a
Ft= +0.11kg*0.5m/s^2
Ft=+0.055N (upward)
Tension will be the difference between Ft and W:
T= Ft-W
T=+0.055N-(-1.078N)
T=+1.133N
Answer:
It only depends on the vertical component
Explanation:
Hello!
The horizontal component will tell you how much you travel in that direction.
You could have a large horizontal velocity, but if the vertical velocity is zero, you will never be out of the ground. Similarly, you could have a zero horizontal velocity, but if you have a non-zero vertical velocity you will be some time off the ground. This time can be calculated by two means, one is using the equation of motion (position as a function of time) and the other using the velocity as a fucntion of time.
For the former you must find the time when the position is zero.
Lets consider the origin of teh coordinate system at your feet
y(t) = vt - (1/2)gt^2
We are looking for a time t' for which y(t')=0
0 = vt' - (1/2)gt'^2
vt' = (1/2)gt'^2
The trivial solution is when t'=0 which is the initial position, however we are looking for t'≠0, therefore we can divide teh last equation by t'
v = (1/2)gt'
Solving for t'
t' = (2v/g)
<span>First you have to convert 7.68 cal/sec to cal/min to do that, just multiply by 60 So it will be 460.8 cal/min now convert that to kcal/min kcal = kilocalories = 1000 calories. so just divide by 1000 and youll have your answer in kcal/min </span>
Answer:
t=240s
Explanation:
Distance=120m
Acceleration=-5m/s^2
v=0
Let u=x m/s
Using equation v^2-u^2=2as:-
0-x=2(-5)(120)
-x=-1200
x=1200m/s
Using now equation v=u+at:-
0=1200+-5t
5t=1200
t=240s
