Answer:
Explanation:
Energy of system of charges
= k q₁q₂ / r₁₂ + k q₁q₃ / r₁₃ + k q₃q₂ / r₃₂
q₁ , q₂ and q₃ are charges and r₁₂ , r₁₃ , r₃₂ are densities between them
9 x 10⁹ ( 2x2 x10⁻¹²/ .25 + 2x2 x10⁻¹²/ .25 + 2x2 x10⁻¹²/ .25 )
= 9 x 10⁹ x 3 x 16 x 10⁻¹²
= 432 x 10⁻³
= .432 J .
Answer:
e)
J
Explanation:
= Magnitude of electric field = 5 V/m
= Area of window = 1.5 m²
= speed of electromagnetic wave = 3 x 10⁸ m/s
= time interval = 1 h = 3600 sec
radiation energy is given as


J
Answer:

Explanation:
It is given that,
Mass of the golf ball, m = 46 g = 0.046 kg
Terminal speed of the ball, v = 44 m/s
The drag force, 
Where, C is the drag coefficient. At terminal speed, the weight of the ball is balanced by the drag force.




Hence, this is the required solution.
Answer:
Option 10. 169.118 J/KgºC
Explanation:
From the question given above, the following data were obtained:
Change in temperature (ΔT) = 20 °C
Heat (Q) absorbed = 1.61 KJ
Mass of metal bar = 476 g
Specific heat capacity (C) of metal bar =?
Next, we shall convert 1.61 KJ to joule (J). This can be obtained as follow:
1 kJ = 1000 J
Therefore,
1.61 KJ = 1.61 KJ × 1000 J / 1 kJ
1.61 KJ = 1610 J
Next, we shall convert 476 g to Kg. This can be obtained as follow:
1000 g = 1 Kg
Therefore,
476 g = 476 g × 1 Kg / 1000 g
476 g = 0.476 Kg
Finally, we shall determine the specific heat capacity of the metal bar. This can be obtained as follow:
Change in temperature (ΔT) = 20 °C
Heat (Q) absorbed = 1610 J
Mass of metal bar = 0.476 Kg
Specific heat capacity (C) of metal bar =?
Q = MCΔT
1610 = 0.476 × C × 20
1610 = 9.52 × C
Divide both side by 9.52
C = 1610 / 9.52
C = 169.118 J/KgºC
Thus, the specific heat capacity of the metal bar is 169.118 J/KgºC
Answer:
(a) B = 5.6 micro Tesla
Explanation:
Current in the wire, i = 140 A
distance, r = 5 m
The formula for the magnetic field at a distance r due to the current carrying wire


B = 5.6 x 10^-6 Tesla
B = 5.6 micro Tesla
(b) As the magnetic field of earth at this site is 20 micro tesla so the magnetic field due to current carrying wire interfere the magnetic compass.