Answer:
W = 8.01 × 10^(-17) [J]
Explanation:
To solve this problem we need to know the electron is a subatomic particle with a negative elementary electrical charge (-1,602 × 10-19 C), The expression to calculate the work is given by:
W = q*V
where:
q = charge = 1,602 × 10^(-19) [C]
V = voltage = 500 [V]
W = work [J]
W = 1,602 × 10^(-19) * 500
W = 8.01 × 10^(-17) [J]
Answer:
13.5
Explanation:
Mass: 5kg
Initial Velocity: -15
Final Velocity: 12
Force: 10
We can use the equation: Vf = Vi + at
We need to find acceleration, and we can use the equation, F=ma,
We have mass and the force so it would look like this, 10=5a, and 5 times 2 would equal 10, so acceleration would be 2.
Now we have all the variables to find time.
Back to Vf = Vi + at, plug the numbers in, 12 = -15 + 2(t)
Plugging them in into desmos gives 13.5 for time.
Question :
If a body acquires a charge of -0.02 C, has it gained or lost electrons? Many?
Solution :
We know, charge gained is shown by negative sign.
Since, charged acquired is given as -0.02 C .
Therefore, it is body has gained electrons.
Now, number of electrons is given by :

Hence, this is the required solution.
Answer:
v ’= 21.44 m / s
Explanation:
This is a doppler effect exercise that changes the frequency of the sound due to the relative movement of the source and the observer, the expression that describes the phenomenon for body approaching s
f ’= f (v + v₀) / (v-
)
where it goes is the speed of sound 343 m / s, v_{s} the speed of the source v or the speed of the observer
in this exercise both the source and the observer are moving, we will assume that both have the same speed,
v₀ = v_{s} = v ’
we substitute
f ’= f (v + v’) / (v - v ’)
f ’/ f (v-v’) = v + v ’
v (f ’/ f -1) = v’ (1 + f ’/ f)
v ’= (f’ / f-1) / (1 + f ’/ f) v
v ’= (f’-f) / (f + f’) v
let's calculate
v ’= (3400 -3000) / (3000 +3400) 343
v ’= 400/6400 343
v ’= 21.44 m / s
Answer:
Explanation:
Energy of a photon = hν , h is plank's constant and ν is frequency .
= h c / λ ; c is velocity of light and λ is wavelength .
= 6.6 x 10⁻³⁴ x 3 x 10⁸ / 550 x 10⁻⁹
= .036 x 10⁻¹⁷ J
Let no of photons be n .
Total energy of n photons
= n x .036 x 10⁻¹⁷ J
Intensity of light = 5 x 10⁻¹² J /m²
Total energy flowing through eye per second
= intensity x area of eye.
= 5 x 10⁻¹² x π x .2² x 10⁻⁴
= .628 x 10⁻¹⁶ J
so
n x .036 x 10⁻¹⁷ = .628 x 10⁻¹⁶
n = .628 x 10⁻¹⁶ / .036 x 10⁻¹⁷
= 17.36 x 10
= 173.6
174.