Answer:
7×160=1120kj so,1120kj=1.12j.
Explanation:
Energy is equal to force times distance,so we add all the distance and we multiply them with the total force of the spring to get the answer. However, the answer is in kilojoules so we have to change it in to joules by dividing the answer into joules by 1000..
Answer:
6.875 m/s
Explanation:
The force is variable which is given by
F(x) = 18 - 0.53 x
mass of the box, m = 8.9 kg
initially it is at rest at x = 0
Let the velocity is v after travelling a distance of 15 m.
According to the work energy theorem, the work done by all the forces is equal to the change in kinetic energy of the body.
Work done = change in kinetic energy



18 x 15 - 0.265 x 15 x 15 = 4.45 x v²
270 - 59.625 = 4.45 v²
v² = 47.275
v = 6.875 m/s
Thus, the final velocity of the box is 6.875 m/s.
Explanation:
Given that,
Radius of the circular loop, r = 3.5 cm = 0.035 m
(a) During a 0.12-s time interval, the magnitude of the field increases uniformly from 0.2 T to 0.5 T. Due to the change in the magnetic field, an emf will induced in it. The magnitude of induced emf is given by :

So, the magnitude of the emf induced in the loop during the time interval is
.
(b) The negative sign shows that the direction of induced emf in the loop is in anitclockwise direction.
Weight : It is the gravitational attraction force on an object near its surface.
It is always measured in the unit of Newton(N)
it is given by the product of mass and acceleration due to gravity

here we know that mass of the pig is m = 140 kg
also we know that acceleration due to gravity near the surface of earth is approximately g = 9.8 m/s/s
so here we know by above formula


so correct answer will be
<em>D. 1372 N</em>