Set the mass of person one at 10 kg and the mass of person two at 10 kg. The two

Q. 1 MWH is equal to ------- joules<br> a.3.6*10^10<br> b.3.6*10^6<br> c.3.6*10^9<br> d.3.6

umka2103 [35]

Correct option is B
1 kWh is equal to 3.6 × 10
6

1 Watt-sec is a Joule a watt expended for a second.
Because there’s 3600 seconds in an hour,
then 3600 Ws = 1 Wh = 3600 Joules = 3.6 kJ
so 1000 Wh = 1 kWh = 1000 × 3.6 kJ = 3.6 MJ = 3.6 × 10
6

5 0

2 years ago

A beaker of vegetable oil contains a beam of light that is aimed at a surface at an angle of 34 degrees as shown. If the index o

Over [174]

Answer:

Angle of reflection of light is 34 degree

Explanation:

As per law of reflection of light we know that

angle of incidence of light = angle of reflection of light

So here we know that

angle of incidence on the surface of oil is given as

$\theta_i = 34 degree$

so we know that

$\theta_i = \theta_r$

so here we can say that reflection angle of light will be same as angle of incidence

$\theta_r = 34 degree$

4 0

3 years ago

a person when asked to speak up,increases her sound level from 30dB to 60dB.The amount of power per unit area increased by? a)30

aivan3 [116]

Answer:

d) 1000 times

Explanation:

As we know that difference of sound level is given as

$L_2 - L_1 = 10 Log \frac{I_2}{I_1}$

so here we need to find the ratio of two intensity

it is given as

$Log\frac{I_2}{I_1} = \frac{(L_2- L_1)}{10}$

$Log\frac{I_2}{I_1} = \frac{60 - 30}{10}$

$Log\frac{I_2}{I_1} = 3$

now we have

$\frac{I_2}{I_1} = 10^3$

so it is

d) 1000 times

4 0

3 years ago

A physics professor demonstrates the Doppler effect by tying a 600 Hz sound generator to a 1.0-m-long rope and whirling it aroun

cluponka [151]

Answer:Highest frequency =618.89Hz

Lowest frequency=582.22Hz

Explanation:

The linear velocity of a sound generator is related to angular velocity and is given as

Vs = rω where

r = the radius of circular path = 1.0 m

ω is the angular velocity of the sound generator. = 100 rpm

1 rev/min = 0.10472 rad/s

100rpm =10.472 rad/ s

Vs = rω

= 1m x 10.472rad/ s= 10.472m/s

A) Highest frequency heard by a student in the classroom = Maximum frequency. Using the Doppler effect formulae,

f max = (v/ v-vs) fs

Where , v is the speed of the sound in air at 20 degrees celcius =

343 metres per second

vs is the linear velocity of the sound generator=10.472m/s

fs is the frequency of the sound generator= 600 Hz

f max = (343/ 343 - 10.472) x 600

=343/332.528) x600

=618.89Hz

B) Lowest frequency heard by a student in the classroom = Minimum frequency

f min = (v/ v+vs) fs

(343/ 343 + 10.472) x 600

=343/353.472) x 600

=582.22hz

5 0

3 years ago

A rock falls from the top of a hill to the bottom. The total energy of the rock at the top isn’t the same as the sum of its pote

mart [117]

Answer:

A) some of the rocks energy is transformed to thermal energy

Explanation:

If we neglect air resistance during the fall of the rock, than the mechanical energy of the rock (which is sum of its potential energy and its kinetic energy) would be constant during the entire motion, so the total energy of the rock at the top would be the same as the sum of its potential energy and kinetic energy at the bottom.

However, this not occurs, due to the presence of air resistance. In fact, air resistance acts against the fall of the rock, and because of the friction between the molecules of air and the surface of the rock, the rock loses part of its energy. This energy is converted into thermal energy of the molecules of the air.

3 0

3 years ago