Answer:
(a). The speed of electron is
.
(b). The radius of electron is 
Explanation:
Given that,
Length = 2.5 cm
Distance = 6.0 mm
Magnetic field = 2.1 T
Potential difference = 700 V
(a). We need to calculate the electron's speed
Using formula of speed

Put the value into the formula



(b). We need to calculate the radius of electron
Using formula of centripetal force


Where,
m = mass of electron
v = speed of electron
r = radius
q = charge of electron
B = magnetic field
Put the value into the formula



Hence, (a). The speed of electron is
.
(b). The radius of electron is 4.2 cm
Answer:
Explanation:
This question pertains to resonance in air column. It is the case of closed air column in which fundamental note is formed at a length which is as follows
l = λ / 4 where l is length of tube and λ is wave length.
here l = .26 m
λ = .26 x 4 = 1.04 m
frequency of sound = 330 Hz
velocity of sound = frequency x wave length
= 330 x 1.04
= 343.2 m /s
b )
Next overtone will be produced at 3 times the length
so next length of air column = 3 x 26
= 78 cm
c )
If frequency of sound = 256 Hz
wavelength = velocity / frequency
= 343.2 / 256
= 1.34 m
= 134 cm
length of air column for resonance
= wavelength / 4
134/4
= 33.5 cm
Answer: Heat engines convert chemical energy to mechanical energy
Explanation: