When an electric current is flowing through a wire, there is a magnetic <em>field</em> produced. The lines of magnetic force are circles around the wire.
Answer:
Explanation:
A proton and electron are moving in the positive x direction, this shows that their velocity will be in the positive x direction
V = v•i
Magnetic field Is the positive z direction
B = B•k
A. For proton.
Proton has a positive charge of q
Direction of force on proton
Force is given as
F = q(v×B)
F = q( v•i × B•k)
F = qvB (i×k)
From vectors i×k = -j
F = -qvB •j
Then, for the positive charge, the force will act in the negative direction of the y-axis
B. For electron
Electron has a negative of -q
Direction of force on proton
Force is given as
F = q(v×B)
F = -q( v•i × B•k)
F = -qvB (i×k)
From vectors i×k = -j
F = --qvB •j
F = qvB •j
Then, for the negative charge, the force will act in the positive direction of the y-axis
Answer: C
Frictional force
Explanation:
The description of the question above is an example of a circular motion.
For a car travelling in a curved path, the frictional force between the tyres and the road surface will provide the centripetal force.
Since the road is banked, and the cross section of the banked road is constructed like a ramp. The car drives transversely to the slope of the ramp, so that the wheels of one side of the car are lower than the wheels on the other side of the car, for cornering the banked road, the car will not rely only on the frictional force.
Therefore, the correct answer is option C - the frictional force.
6. Drop to one quarter of its original value
The motion of planets is separate to the motion of stars. Like everything in the sky, they rise in the east, and set in the west, because of the earth's rotation. But night by night, their position at a given time changes because of their orbit around the sun.