Answer:
<h2> $1.50</h2>
Explanation:
Given data
power P= 2 kW
time t= 15 min to hours = 15/60= 1/4 h
cost of power consumption per kWh= 10 cent = $0.1
We are expected to compute the cost of operating the heater for 30 days
but let us computer the energy consumption for one day
Energy of heater for one day= 2* 1/4 = 0.5 kWh
the cost of operating the heater for 30 days= 0.5*0.1*30= $1.50
<u><em>Hence it will cost $1.50 for 30 days operation</em></u>
Answer:
5.65 times
Explanation:
60 db sound is equal to 60 phons sound when frequency is kept at 1000Hz.
But when the frequency of sound is changed to 100 Hz , according to equal loudness curves , the loudness level on phon scale will be 35 phons.
A decrease of 10 phon on phon- scale makes sound 2 times less loud
Therefore a decrease of 25 phons will make loudness less intense by a factor equal to 2²°⁵ or 5.65 less intense . Therefore intensity at 100 Hz
must be increased 5.65 times so that its intensity matches intensity of 60 dB sound at 1000 Hz frequency.
When light is reflected by a mirror, the angle of incidence is always <span>A. equal to the angle of reflection. We know this by the Law of Reflection.</span>
Answer:Its B
Explanation:Trust Me i done This Before
Answer:
Explanation:
The time period of the pendulum containing simple pendulum is given by
where, L is the length of the pendulum and g is the value of acceleration due to gravity.
The time period of the clock using the spring mechanism is given by
where, m is the mass of the block attached to the spring and k is the spring constant.
here we observe the time period of the pendulum depends on the value of acceleration due to gravity. The value of acceleration due to gravity decreases as we go on the heights that means when the clock is taken to the mountain, the value of g decreases and thus, the value of time period increases and the clock runs slow.
So, the clock containing the spring system gives the accurate reading rather than the clock containing simple pendulum.
