The magnetic force on the electron is:

where q is the electron charge, v the electron speed, B the magnetic field intensity and

is the angle between v and B. Since the electron is traveling perpendicular to the magnetic field,

, so we can write

This force acts as centripetal force of the motion,

, where m is the electron mass and r the radius of the circular orbit. So we can write:

and by re-arranging this equation, we find the radius of the circular orbit, r:
Answer:
a)
840 N
b)
10920 J
c)
- 10192 J
d)
4.3 m/s
Explanation:
a)
T = tension force in the cable in upward direction = ?
a = acceleration of the person in upward direction = 0.70 m/s²
m = mass of the person being lifted = 80 kg
Force equation for the motion of person in upward direction is given as
T - mg = ma
T = m (g + a)
T = (80) (9.8 + 0.70)
T = 840 N
b)
d = distance traveled in upward direction = 13 m
= Work done by tension force
Work done by tension force is given as
= T d
= (840) (13)
= 10920 J
c)
d = distance traveled in upward direction = 13 m
= Work done by person's weight
Work done by person's weight is given as
= - mg d
= - (80 x 9.8) (13)
= - 10192 J
d)
= Net force on the person = ma = 80 x 0.70 = 56 N
v₀ = initial speed of the person = 0 m/s
v = final speed
Using work-energy theorem
d = (0.5) m (v² - v₀²)
(56) (13) = (0.5) (80) (v² - 0²)
v = 4.3 m/s
Answer:
Along the western side of the Coast Range the climate is dominated by the Pacific Ocean. Warm winters, cool summers, small daily and seasonal temperature ranges, and high relative humidities are characteristic of this area.
Explanation:
Answer:B
Explanation:
Given
Distance of astronaut From asteroid x is 
Distance of astronaut From asteroid Y is 
Suppose M,M_x,M_y be the masses of Astronaut , asteroid X and Y
If the astronaut is in equilibrium then net gravitational force on it is zero


cancel out the common terms we get




Using the 2nd equation of motion;
= s = ut + ½at²
= 40 = u×2 + ½ × 6 × 2²
= 40 = 2u + 3 × 4
= 40 - 12 = 2u
= 28/2 = u
= 14 m/s = u
And its done! Simple isn't? :P