Answer:
Explanation:
Given that,
B(t) = B0 cos(ωt) • k
Radius r = a
Inner radius r' = a/2 and resistance R.
Current in the loop as a function of time I(t) =?
Magnetic flux is given as
Φ = BA
And the Area is given as
A = πr², where r = a/2
A = πa²/4
Then,
Φ = ¼ Bπa²
Φ(t) = ¼πa²Bo•Cos(ωt)
Then, the EMF is given as
ε(t) = -dΦ/dt
ε(t) = -¼πa²Bo • -ωSin(ωt)
ε(t) = ¼ωπa²Bo•Sin(ωt)
From ohms law,
ε = iR
Then, i = ε/R
I(t) = ¼ωπa²Bo•Sin(ωt) /R
This is the current induced in the loop.
Check attachment for better understanding
Answer:
D.
R increases
V is constant
I decreases
Explanation:
The resistance of a wire is given by the following formula:
It is clear from this formula that resistance is directly proportional to the length of wire. So, when length of wire is increased, <u>the resistance of circuit increases</u>.
The <u>voltage in the circuit will be constant</u> as the voltage source remains same and it is not changed.
Now, we can use Ohm Law:
V = IR
at constant V:
I ∝ 1/R
it means that current is inversely proportional to resistance. Hence, the increase of resistance causes <u>the current in circuit to decrease.</u>
Therefore, the correct option will be:
<u>D.</u>
<u>R increases
</u>
<u>V is constant
</u>
<u>I decreases</u>
Answer:
Explanation:
As it’s difficult to catch it from up.
Gravitational force will pull us when we jump.
If gravity was not there, he could catch the ball. But he will float in the sky after that.
That’s the answer
Explanation:
A centripetal force (from Latin centrum, "center" and petere, "to seek") is a force that makes a body follow a curved path. (not sure but hope this helps )
<span>"Does lack of sunlight affect plant growth?"
This question can be investigated with procedures according to
the Scientific Method, because "lack of sunlight" can be arranged
unambiguously, and "affected plant growth" can be identified
unambiguously.
The other questions involve words or phrases with ambiguous definitions,
that can mean different things to different people, and would be hard to
agree on, like "</span><span>best advice", "sound quality", and "happiness in life".</span>
