Answer:
The current in the heater is 12.5 A
Explanation:
It is given that,
Power of electric heater, P₁ = 1400 W
Power of toaster, P₂ = 1150 W
Power of electric grill, P₃ = 1560 W
All three appliances are connected in parallel across a 112 V emf source. We need to find the current in the heater. We know that in parallel combination of resistors the current flowing in every branch of resistor divides while the voltage is same.
Electric power, 
So, the current in the heater is 12.5 A. Hence, this is the required solution.
Answer:
a ) 2.68 m / s
b ) 1.47 m
Explanation:
The jumper will go down with acceleration as long as net force on it becomes zero . Net force of (mg - kx ) will act on it where kx is the restoring force acting in upward direction.
At the time of equilibrium
mg - kx = 0
x = mg / k
= (60 x 9.8 ) / 800
= 0.735 m
At this moment , let its velocity be equal to V
Applying conservation of energy
kinetic energy of jumper + elastic energy of cord = loss of potential energy of the jumper
1/2 m V² + 1/2 k x² = mg x
.5 x 60 x V² + .5 x 800 x .735 x .735 = 60 x 9.8 x .735
30 V² + 216.09 = 432.18
V = 2.68 m / s
b ) At lowest point , kinetic energy is zero and loss of potential energy will be equal to stored elastic energy.
1/2 k x² = mgx
x = 2 m g / k
= (2 x 60 x 9.8) / 800
= 1.47 m
Answer:
The intensity increased by a factor of 158489
Explanation:
Given that,
Sound level = 95.0 dB
Sound level = 43.0 dB
Frequency = 10000 Hz
We need to calculate the ratio of sound intensity
Using formula of sound level
Put the value into the formula
...(I)
.....(II)
Subtracting these equations
Taking inverse log
Hence, The intensity increased by a factor of 158489
Answer:
i = 61 degree
Explanation:
Given,
Now, by the snell's law
Now,
Sin i / sin r = n 2 / n 1
sin i / sin r (45 - 24.09) = 2.45 / 1
i = 60.97 degree
Answer:
Explanation:
We know that from Newton's second law of motion, F=ma hence making acceleration the subject then 
where a is acceleration, F is force and m is mass
Also making mass the subject of the formula 
For 
and 
hence 
