As per energy conservation we know that
Energy enter into the bulb = Light energy + Thermal energy
so now we have
energy enter into the bulb = 100 J
Light energy = 5 J
now from above equation we have
Answer:
correct answers C
Explanation:
the electric field is derived from Coulomb's law, where the charge has been assumed to be positive.
The expression remains
F = k q₁ q / r²
the electric field is
Fe = (k q₁ / r²) q
The amount between parentises rs constant
by checking the correct answers C
Answer:
acceleration a = 1.04 m/s2
Explanation:
Assume the train has a speed of 23m/s when the last car passes the railway workers. Once this happens the last car would have traveled a total distance of the 180m distance between the railway worker standing 180 m from where the front of the train started plus the 75m distance from the first car to the last car:
s = 75 + 180 = 255 m
We can use the following equation of motion to find out the distance traveled by the car:
where v = 23 m/s is the velocity of the car when it passes the worker, = 0m/s is the initial velocity of the car when it starts, a m/s2 is the acceleration, which we are looking for.
Answer:
the output power of the hearing aid in two significant figures is 3.2 × 10⁻⁸ W
Explanation:
Output power of sound is given as;
P = I*A
where;
I is the sound intensity = 90dB = 1 × 10⁻³ W/m²
A is the area through which the transmits;
since the canal is circular in shape.
Given;
D as diameter = 6.4mm = 0.0064 m
Output power of the hearing aid = (1 × 10⁻³ W/m²)*(3.217 × 10⁻⁵ m²)
= 3.2 × 10⁻⁸ W
Therefore, the output power of the hearing aid in two significant figures is 3.2 × 10⁻⁸ W.