I believe that the answer is B. 133 N
Answer: g = 10.0 m/s/s
Explanation:
For a simple pendulum, provided that the angle between the lowest and highest point of his trajectory be small, the oscillation period is given by the following expression:
T = 2π √L/g , where L = pendulum length, g= accelleration of gravity.
We can also define the period, as the time needed to complete a full swing, so from the measured values, we can conclude the following :
T = 140 sec/ 101 cycles = 1.39 sec
Equating both definitions for T, we can solve for g, as follows:
g = 4 π² L / T² = 4π². 0.49 m / (1.39)² = 10.0 m/s/s
We use formula, the volume of aluminium
Given, , and
Substituting these values, we get
.
Thus, the thickness of the aluminium foil is 2.55 mm.
Given:
length of the wire = 0.20 meters
magnetic field strength = 0.45 newtons/amperes meter
speed = 10.0 meters per second
emf = B * l * v
B = flux density ; l = length of the wire ; v = velocity of the conductor
emf = 0.45 newtons / ampere meter * 0.20 meters * 10.0 meters/seconds
emf = 0.90 volts
The emf produced is 0.90 volts.