If a light ray from a candle strikes a mirror at an angle of 40° with the normal, at what angle will the ray reflect?

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olga nikolaevna [1]

Answer:

¿

Explanation:

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4 0

2 years ago

Driving on asphalt roads entails very little rolling resistance, so most of the energy of the engine goes to overcoming air resi

Bad White [126]

A) Agreed.
b) Value agreed but units should be W (watts). 

c) Here's one method... 

15 miles = 24140 m 

1 gallon of gasoline contains 1.4×10⁸ J. 

So moving a distance of 24140m requires gasoline containing 1.4×10⁸ J 

Therefore moving a distance of 1m requires gasoline containing 1.4×10⁸/24140 = 5800 J 

Overcoming rolling resitance for 1m requires (useful) work = force x distance = 1000x1 = 1000J 

So 5800J (in the gasoline) provides 1000J (overcoming rolling resistance) of useful work for each metre moved. 

Efficiency = useful work/total energy supplied 
= 1000/5800 
= 0.17 (=17%)

8 0

3 years ago

What type of change is wood to wood chip?

Vanyuwa [196]

Answer:

irriversible change.....

4 0

2 years ago

Read 2 more answers

Space-faring astronauts cannot use standard weight scales (since they are constantly in free fall) so instead they determine the

valentinak56 [21]

Answer:

ma = 48.48kg

Explanation:

To find the mass of the astronaut, you first calculate the mass of the chair by using the information about the period of oscillation of the empty chair and the spring constant. You use the following formula:

$T=2\pi\sqrt{\frac{m_c}{k}}$ (1)

mc: mass of the chair

k: spring constant = 600N/m

T: period of oscillation of the chair = 0.9s

You solve the equation (1) for mc, and then you replace the values of the other parameters:

$m_c=\frac{T^2k}{4\pi^2}=\frac{(0.9s)^2(600N/m)}{4\pi^2}=12.31kg$ (2)

Next, you calculate the mass of the chair and astronaut by using the information about the period of the chair when the astronaut is sitting on the chair:

T': period of chair when the astronaut is sitting = 2.0s

M: mass of the astronaut plus mass of the chair = ?

$T'=2\pi\sqrt{\frac{M}{k}}\\\\M=\frac{T'^2k}{4\pi^2}=\frac{(2.0s)^2(600N/m)}{4\pi^2}\\\\M=60.79kg$ (3)

Finally, the mass of the astronaut is the difference between M and mc (results from (2) and (3)) :

$m_a=M-m_c=60.79kg-12.31kg=48.48kg$

The mass of the astronaut is 48.48 kg

3 0

3 years ago

A truck is moving at a constant speed of 50 m/s. A boy riding in the back of the truck throws a newspaper out the back of the tr

lbvjy [14]

Answer:

70m/s

Explanation:

7 0

3 years ago