Answer:
Explanation:
Acceleration roughly means “change in velocity.” If this change in velocity is consistently in one direction, the body will reach a point at which its velocity is zero.
Another consideration is when you drop a basketball onto the pavement. The ball falls, hits the ground, and comes back up. Because its direction of motion changed, you know that its velocity MUST have been 0 m/s at some point during the bounce.
This doesn't mean there was no acceleration at this point.
Answer:
Explanation:
magnetic filed, B = 0.65 T
initial diameter, d = 17.5 cm
final diameter, d' = 6.6 cm
time, t = 0.48 s
(a) According to Lenz's law, the direction of induced current is clockwise.
(b) Let e is the induced emf.
initial area, A = π r² = 3.14 x 0.0875 x 0.0875 = 0.024 m²
final area, A' = π r'² = 3.14 x 0.033 x 0.033 = 0.00342 m²
change in area, ΔA = A - A' = 0.024 - 0.00342 = 0.02058 m²
The magnitude of induced emf is given by
![e=\frac{d\phi }{dt}](https://tex.z-dn.net/?f=e%3D%5Cfrac%7Bd%5Cphi%20%7D%7Bdt%7D)
![e=B\frac{\Delta A }{dt}](https://tex.z-dn.net/?f=e%3DB%5Cfrac%7B%5CDelta%20A%20%7D%7Bdt%7D)
e = 0.65 x 0.02058 / 0.48
e = 0.028 V
(c) R = 2.5 ohm
i = e / R
i = 0.028 / 2.5
i = 0.011 A
Answer:
A) equal to the battery's terminal voltage.
Explanation:
When the capacitor is fully charged after long hours of charging , its potential becomes equal to the emf of the battery and its polarity is opposite to that of battery . Hence net emf becomes equal . The capacitor itself becomes a battery which is connected in the circuit with opposite polarity . This results in the net emf and current becoming zero . There is no charging current when the capacitor is fully charged .
The largest value of current that the breaker can carry = Imax=35.4A
Explanation:
Rms value of current= Irms= 25 A
The rms current and the maximum current are related as
Imax= √2 Irms
Imax=√2 (25)
Imax=35.4 A
Thus the maximum current carried by the breaker= 35.4 A
Answer:
L = 130 decibels
Explanation:
The computation of the sound intensity level in decibels is shown below:
According to the question, data provided is as follows
I = sound intensity = 10 W/m^2
I0 = reference level = ![1 \times 10-12 W/m^2](https://tex.z-dn.net/?f=1%20%5Ctimes%2010-12%20W%2Fm%5E2)
Now
Intensity level ( or Loudness)is
![L = log10 \frac{I}{10}](https://tex.z-dn.net/?f=L%20%3D%20log10%20%5Cfrac%7BI%7D%7B10%7D)
![L = log10 \frac{10}{1\times 10^{-12}}](https://tex.z-dn.net/?f=L%20%3D%20log10%20%5Cfrac%7B10%7D%7B1%5Ctimes%2010%5E%7B-12%7D%7D)
![L = log10 \times 1013](https://tex.z-dn.net/?f=L%20%3D%20log10%20%5Ctimes%201013)
![= 13 \times 1 ( log10(10) = 1)](https://tex.z-dn.net/?f=%3D%2013%20%5Ctimes%201%20%28%20log10%2810%29%20%3D%201%29)
Therefore
L = 13 bel
And as we know that
1 bel = 10 decibels
So,
The Sound intensity level is
L = 130 decibels