Answer:
Option E is correct 310N
Explanation:
Given that the force used to push the crate is F = 200N
The force directed 20° below the horizontal
Mass of crate is m = 25kg
Weight of the crate can be determine using
W = mg
g is gravitational constant =9.8m/s²
W = 25×9.8
W = 245 N
Check attachment. For free body diagram and better understanding
Using newton second law along the vertical axis since we want to find the normal force
ΣFy = m•ay
ay = 0, since the body is not moving in the vertical or y direction
N—W—F•Sin20 = 0
N = W+F•Sin20
N = 245+ 200Sin20
N = 245 + 68.4
N = 313.4 N
The normal force is approximately 310 N to the nearest ten
Answer:
8.79*10^6 rad/s
Explanation:
To find the frequency of the circular orbit for an electron you use the following expression, for the radius of the trajectory of an electron, that travels trough a constant magnetic field:
(1)
r: radius of the trajectory
m: mass of the electron = 9.1*10^-31 kg
v: speed of the electron = 1.0*10^6 m/s
q: charge of the electron = 1.6*10^-19 C
B: magnitude of the magnetic field = 5.0*10^-5 T
You use the fact that the angular frequency in a circular motion is given by:

Then, you solve the equation (1) in order to obtain v/r:

Finally, you replace the values of the parameters:

hence, the angular frequency is 8.79*10^6 rad/s
The frequency is:
