It is fairly easy to build an electromagnet. All you need to do is wrap some insulated copper wire around an iron core. If you attach a battery to the wire, an electric current will begin to flow and the iron core will become magnetized. When the battery is disconnected, the iron core will lose its magnetism. Follow these steps.
Step 1 - Gather the Materials
One iron nail fifteen centimeters (6 in) long
Three meters (10 ft) of 22 gauge insulated, stranded copper wire
One or more D-cell batteries
Step 2 - Remove some Insulation
Step 3 - Wrap the Wire Around the Nail
Step 4 - Connect the Battery
Answer:
Force, 
Explanation:
Given that,
Mass of the bullet, m = 4.79 g = 0.00479 kg
Initial speed of the bullet, u = 642.3 m/s
Distance, d = 4.35 cm = 0.0435 m
To find,
The magnitude of force required to stop the bullet.
Solution,
The work energy theorem states that the work done is equal to the change in its kinetic energy. Its expression is given by :
Finally, it stops, v = 0
F = -22713.92 N
So, the magnitude of the force that stops the bullet is 
The ratio of the distance moved by the point at which the effort is applied in a simple machine to the distance moved by the point at which the load is applied, in the same time. In the case of an ideal (frictionless and weightless) machine, velocity ratio = mechanical advantage. Velocity ratio is sometimes called distance ratio.
Answer:
0.84 s
Explanation:
Step 1
Given information:
Mass of the ice (m) = 2.0 kg
Heat transfer rate (Q/T) = 793.0 kW
Latent heat of fusion of ice (Lf) = 334 kJ/kg
Substituting the corresponding values we have:
The SI unit of force is the Newton.
1 newton is the force that accelerates a 1 kilogram mass
at the rate of 1 meter per second².
1 pound of force is equivalent to roughly 4.448 newtons.
(1 newton is equivalent to roughly 0.225 pounds of force.)
