Answer:
Explanation:
Electron's kinetic energy = 2 eV
= 2 x 1.6 x 10⁻¹⁹ J
1/2 m v² = 3.2 x 10⁻¹⁹
1/2 x 9.1 x 10⁻³¹ x v² = 3.2 x 10⁻¹⁹
v² = .703 x 10¹²
v = .8385 x 10⁶ m/s
Electrons revolve in a circular orbit when forced to travel in a magnetic field whose radius can be expressed as follows
r = mv / Bq
where m , v and q are mass , velocity and charge of electron .
here given magnetic field B = 90 mT
= 90 x 10⁻³ T
Putting these values in the expression above
r = mv / Bq
= 
= .052 mm.
F = 1/t
F = 1/0.5
F = 2Hz
Answer is 2Hz
Answer:
The rate of the boat in still water is 44 mph and the rate of the current is 4 mph
Explanation:
x = the rate of the boat in still water
y = the rate of the current.
Distance travelled = 120 mi
Time taken upstream = 3 hr
Time taken downstream = 2.5 hr
Speed = Distance / Time
Speed upstream

Speed downstream

Adding both the equations


The rate of the boat in still water is <u>44 mph</u> and the rate of the current is <u>4 mph</u>
Answer:
Formation of a Precipitate
Unexpected Color Change
Formation of a Gas
Explanation:
Answer:
used in telescope, glasses, cameras, flashlights, peepholes
Explanation:
Concave lens curve inward so they cause light to spread out.