Answer:
20 m/s
Explanation:
Recall that one of the equations of motions can be written:
v = u + at, (also see attached for reference)
Where,
v = final speed (we are asked to find this)
u = initial speed = 0 (because it starts from rest)
t = time taken = 5s
We simply substitute the given values into the equation:
v = u + at
v = 0 + (4)(5)
v = 20 m/s
Tetraphosphorus disulfide
- R3KTFORGOOD ☕
Answer:
B. A magnet being moved into or out of the coil
Explanation:
Faraday law of electromagnetic induction states that when there is change in flux , an emf is produced . Among the given instances , only in case of B , flux is changing . So current will be induced in the coil . We shall see how it takes place .
A wire carrying constant current will produce magnetic flux in nearby coil but there is no change in flux because current as well as position of wire with respect to coil are not changing .
Passing of magnetic field through a stationary coil produces flux in the coil but here too there is no change in flux so no current will be induced .
A magnet positioned near a coil creates magnetic flux in the coil but the magnitude of flux remains constant so no change in flux and no creation of induced current .
Answer/Explanation:
Acceleration is the rate of change of the velocity of an object that is moving. This value is a result of all the forces that is acting on an object which is described by Newton's second law of motion. Calculation of such is straightforward, if we are given the final velocity, the initial velocity and the total time interval. We can just use the kinematic equations. Fortunately, we are given these values. So, we calculate as follows:
acceleration = v - v0 / t
acceleration = (80 mph - 50 mph) ( 1 h / 3600) / 5 s
acceleration = 1.67 x 10^-3 m / s^2
An inclined plane would not be practical because he would still have to push it and the amount of effort and energy would increase. A lever would not be practical because he would have to use his weight to make the bale rise 15 feet. He would also need to make sure that he has a 15 foot ladder in the first place. A screw would not be practical because he would have to drill a hole through the medium and use rotation.
A
pulley would be the most practical way of moving the cotton bale. A
pulley supports movement and will help the farmer move the bale.
