Answer:
a) 1450watts
b) 564watts
c) 1.11
Explanation:
Power consumed = IV
I is the current rating
V is the operating voltage
If a blow-dryer and a vacuum cleaner each operate with a voltage of 120 V and the current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 4.7 A then their individual power rating is calculated thus;
a) For blow-dryer
Operating voltage = 120V
Its current rating = 12A
Power consumed = IV
= 120×12
= 1440watts
b) For vacuum cleaner:
Operating voltage is the same as that of blow dryer = 120V
Its current rating = 4.7A
Power consumed = IV
= 120×4.7
= 564watts
c) Energy used = Power consumed × time taken
Energy used = Power × time
Energy used by blow dryer = 1440×20×60
= 1,728,000Joules
Energy used up by vacuum cleaner = 564×46×60
= 564×2760
= 1,556,640Joules
Ratio of the energy used by the blow-dryer in 20 minutes to the energy used by the vacuum cleaner in 46 minutes will be 1,728,000/1,556,640 = 1.11
Answer:
D . Sound energy
Explanation:
When the strings of a violin vibrate it produces sound which is sound energy. Due to the vibration of the strings the air present near the strings also vibrate in resonance with the strings. This compreesion and decompression's produced in the air is nothing but the sound. So the form of energy given off by the vibrating strings of the violin is Sound energy.
Answer:
20.60 kV
Explanation:
Capacitance of parallel plates without dielectric between them is:
with d the distance between the plates, A the area of the plates and ε₀ the constant 
, so :
But the dielectric constant is defined as:
With C the effective capacitance (with the dielectric) and Co the original capacitance (without the dielectric). So, the new capacitance is:
But capacitance is related with voltage by:
with Q the charge and V the voltage, using the new capacitance and solving for V:
Particles transfer energy physically from one to the other either horizontally in a longitudinal wave, vertically in a transverse wave, or in circles in a surface wave. Waves can also be electromagnetic, which are always transverse and do not require a medium to propagate, like light waves traveling through space.
Answer:
Explanation:
mechanical advantage = output force / input force
= 740 N / 55 N
= 13.45
