Search & Filtering
. An electron is accelerated through 2 400 V from rest and then enters a uniform 1.70-T magnetic field. What are (a) the maximum and (b) the minimum values of the magnetic force this particle can experience?
On a 200 km bike cycle ride, you ride the first 90 km at an average speed of 20m/s. What must your average speed over the next 40 km to be have your average speed for the total 200 km be?
a. 60m/s.
b. Given this average speed for the first 90 km, can you possibly attain an average speed of 80 m/s for the total 200 km ride? Explain.
Given three vectors A = 24i + 33j, B = 55i - 12j and C = 2i + 43j
(a) Find the magnitude of each vector.
(b) Write an expression for the vector difference A - C.
(c) Find the magnitude and direction of the vector difference A-B.
(d) In a vector diagram show vector A + B, and A - B, and also show that your diagram agrees
A person is riding on a flatcar traveling at a constant speed of 200 km/s (Fig.). He wishes to throw
a ball through a stationary hoop 90 km above the height of his hands in such a manner that the ball
will move horizontally as it passes through the hoop. He throws the ball with a speed of 250 m/s
with
respect to himself,
(a) How many time required after he releases the ball will it pass through the hoop?
(b) What must the vertical component of the initial velocity of the ball?
(c) At what horizontal distance in front of the hoop must he release the ball?
(d) When the ball leaves the man's hands, what is the direction of its velocity relative to the
frame of reference of the flatcar? Relative to the frame of reference of an observer standing
on the ground?
90 km
V
V
X
v = 200 km/s
A driver at Dewaan Motors is testing a new model car with a speedometer calibrated to read m/s
rather than km/h. The following series of speedometer readings was obtained during a test run
along a long, straight road:
Time (s)
Speed (m/s)
0 1 3 5 7 9
0 0 4 7 10 13
15
17
19
11 13
17 22
23
26
29
(a) Compute the average acceleration during each 2-s interval. Is the acceleration constant? Is it
constant during any part of the test run?
(b) Make a (v-t) graph of the data, using scales of 1cm = 1s horizontally and 1cm = 2m/s
vertically. Draw a smooth curve through the plotted points. By measuring the slope of your
curve, find the instantaneous acceleration at t = 6 s, 18 s, and 25 s.
The Earth and the Moon may be considered to be uniform spheres that are isolated in space. The Earth has radius R and mean density ρ. The Moon, mass m, is in a circular orbit about the Earth with radius nR,
The Moon makes one complete orbit of the Earth in time T.
Show that the mean density ρ of the Earth is given by the expression
ρ = 3πn^3/GT^2
Calculate the mass of the earth if the radius is approximately 6400km, if g=9.8m/s² and G=6.7×10–11Nm²kg–²
.
A rectangular metal waveguide filled with a dielectric of relative permittivity εr = 4, has the inside dimensions 3 x 1.2 cm, the cut off frequency for the dominant mode is
Find the radiation resistance of an antenna of length λ/10 meter?
find electric field at center of square q=11.8 nC AND a=5.20cm
