Friction is the force you get when you (for example) Rub something with another, it's a force that may generate heat and even some resistance. Another example is rubbing your hands together, they get hot, therefore friction is working, without friction you wouldn't be able to stop moving.
mass gram, time sec, temp kelvin, vol liter, dens grams/cm3
Answer:
A solenoid is a device comprised of a coil of wire, the housing and a moveable plunger (armature). When an electrical current is introduced, a magnetic field forms around the coil which draws the plunger in. More simply, a solenoid converts electrical energy into mechanical work.
Explanation:
The coil is made of many turns of tightly wound copper wire. When an electrical current flows through this wire, a strong magnetic field/flux is created.
The housing, usually made of iron or steel, surrounds the coil concentrating the magnetic field generated by the coil.
The plunger is attracted to the stop through the concentration of the magnetic field providing the mechanical force to do work.
Answer:
2000 V/m
1778021.69323 m/s
Explanation:
V = Voltage = 9 V = 
q = Charge of proton = 
m = Mass of electron = 
v = Velocity of electron
Electric field is given by

The electric field is 2000 V/m
Here, the energy of the system is conserved

The velocity of the electron is 1778021.69323 m/s