Answer:
Terminal speed, v = 6901.07 m/s
Explanation:
It is given that,
Mass of the horizontal bar, m = 30 g = 0.03 kg
Length of the bar, l = 13 cm = 0.13 m
Magnetic field, 
Resistance, R = 1.2 ohms
We need to find the terminal speed oat which the bar falls. When terminal speed is reached,
Force of gravity = magnetic force
..................(1)
i is the current flowing
l is the length of the rod
Due to the motion in rods, an emf is induced in the coil which is given by :
, v is the speed of the bar
Equation (1) becomes,
v = 6901.07 m/s
So, the terminal speed at which the bar falls is 6901.07 m/s. Hence, this is the required solution.
Making cars that get better gas mileage
Answer:
f2 = 140 Hz
Explanation:
let fundamental frequency is f1 = 70.0 Hz
formula for finding the higher frequency when fundamental frequency is known
fn = n f1 (where f1 is fundamental frequency and n = 1,2,3,4,5...........)
for the second frequency n=2
f2 = 2 × 70.0 Hz
f2 = 140 Hz
You've already told us the speed in ft/s . It's right there in the question. You said that light travels about 982,080,000 ft/s.
We don't know how accurate that number is, but for purposes of THIS question, that's the number we're going with.
In scientific notation, it's written . . . <em>9.8208 x 10⁸ ft/s .</em>
We don't know where you were going with the number of seconds in a year. But to answer the question that you eventually asked, it turned out that we don't even need it.
Velocity, as it is is a vector quantity, so it has both direction and magnitude.
Speed is a scalar quantity, so it only has magnitude, no direction.
