Acceleration = (change in speed) / (time for the change)
Change in speed = (speed at the end) - (speed at the beginning)
= (140 km/hr) - (10 km/hr) = 130 km/hr
Time for the change = 50 sec
Acceleration = (130 km/hr) / (50 sec) = 2.6 km/hr per second.
To convert to more familiar units:
(2.6 km/hr-sec) x (1000 m/km) x (1 hr/3600 sec)
= (2.6 x 1000 x 1) / (3600) km-m-hr / hr-sec-km-sec
= 0.722 m/s² (about 0.074 of a G)
Answer: 0.048 J
Explanation:
The described situation is better understood with the attached figure.
Let's assume that when the mass is released after being lifted up, it starts performing simple harmonic motion with an amplitude L. Then, the maximum speed of this hanging mass is fulfilled at the equilibrium position and its given by the following equation:
(1)
Where:
is the spring constant which can be calculated by the Hooke's law: being the acceleration due gravity and the length the spring is streched.
is the mass
is the amplitude
So, (2)
Substituting (2) in (1):
(3)
(4)
On the other hand, the kinetic energy is given by the following equation:
(5)
(6)
Hence:
Answer:
work output is always less than work input - the ratio is less than 1.
Explanation:
This principle comes from the fact that a machine or system cannot produce more work than is supplied to it, because this would violate the energy conservation law (work is a type of mechanical energy).
In theoretical machines called "ideal machines" the input work is the same as the output work, but these machines are only theoretical because in real applications there is always some type of energy loss, either in heat produced by a machine or processes for its operation, for this reason the output work is always less than the input work.
Regarding the ratio work output to work input:
because work input WI is always greater than work output WO.
Answer:
This is a paradox — an inconsistency that often leads people to think that time travel cannot occur in our universe." A variation is known as the "grandfather paradox" — in which a time traveler kills their own grandfather, in the process preventing the time traveler's birth
Explanation:
hope this Wil help ....
Let FAB, be the force exerted on body B by body A and FBA be the force exerted by body B on A. Suppose that due to these forces FAB and FBA, dp1/dt and dp2/dt be the rate of the change of momentum of these bodies respectively.