Answer:
a) E = 0.0048 Volts
b) dA/dt = - 0.002285 m²/s
Explanation:
Given:
Area, A = 0.020 m²
Rate of change of magnetic field, dB/dt = 0.24 T/s
a) The magnitude of the emf induced (E) is given as:
E= A × (dB/dt)
on substituting the values in the above equation, we get
E = (0.020 m²) × (0.24 T/s)
or
E = 0.0048 Volts
b) Now, The induced emf when both the area and the magnetic field is varying
we have
E = B(dA/dt) + A(dB/dt)
Now, for the given case induced emf is zero i.e E = 0 and magnetic field B = 2.1 T
thus,
0 = (2.1 T)(dA/dt) + (0.020 m2)(0.24 T/s)
dA/dt = - 0.002285 m²/s
Hence, the area should be decreased at the rate of 0.002285 m²/s
There are several information's already given in the question. Based on those information's the answer can be easily deduced.
Distance traveled by the bicycle rider = 50 km
Time taken to travel the distance = 2.5 hours
So
In 2.5 hours the bicycle rider travels = 50 km
Then
In 1 hour the bicycle rider travels = 50/2.5
= 20 km
Then the average speed of the cyclist is 20 km per hour.
1.) Use the formula to solve -
1/f = 1/do + 1/di; Where f = focal length; 1/do + 1/di
1/f = 1/do + di
1/8 = 1/25 + 1/?
.125 = .04 + 1/di
.125 -.04 = 1/di (transferred .04 to the left side of the equation)
.085/1 = 1/di
.085di/.085 = 1/.085 (multiplied both sides by di and divided both sides by .085)
di = 11.76 or 12
2.) Therefore, 12 cm is the distance from the image to the mirror
An element with a valence of 8 are most likely noble gases (He, Ne, Ar, etc) which means they're already stable so they dont need to undergo chemical bonds with another atom because they already have a full valence shell.