Answer:
The magnetic field through the wire must be changing
Explanation:
According to Faraday's law, the induced emf, ε in a metallic conductor is directly proportional to the rate of change of magnetic flux,Φ through it. This is stated mathematically as ε = dΦ/dt.
Now for the wire, the magnetic flux through it is given by Φ = ABcosθ where A = cross-sectional area of wire, B = magnetic field and θ = angle between A and B.
So, dΦ/dt = dABcosθ/dt
Since A and B are constant,
dΦ/dt = ABdcosθ/dt = -(dθ/dt)ABsinθ
Since dθ/dt implies a change in the angle between A and B, since A is constant, it implies that B must be rotating.
So, <u>for an electric current (or voltage) to be produced in the wire, the magnetic field must be rotating or changing</u>.
Energy can be changed from one form to another, but it cannot be created or destroyed. ... This principle is referred to as the first law of thermodynamics or the law of energy conservation. The law applies to all systems both large and small, and, again, it states that energy cannot be created or destroyed.
Answer:
Yes
Explanation:
Yes. The momentum is the same when the speed of the tennis ball is 18 times greater than the speed of the basketball and the velocities of both objects are in the same direction.
Answer:
Explanation:
Givens
d = 115 km
r = 80 km/hr
t = ?
Equation
d = r*T
Solution
115 = 80 * t Divide by 80
115/80 = t
t = 1.4375 hours.
Answer:
c. selenium
Explanation:
sulfur and selenium are in the same group