Calculate the amount of energy transferred when a 40w light bulb is left on for 30 minutes.

In both the camera and the __________, light enters a narrow opening and is projected onto a photosensitive surface. Group of an

Citrus2011 [14]

Answer: The HUMAN EYE

Explanation:

The human eye is made up of different parts which ranges from controlling the amount of light that enters the eye to the focusing of the image that is formed. The camera is a device which is both mechanically and electronically operated which shares a number of similarities with the eye.

In the human eye, the IRIS helps to regulate the amount of rays passing through the pupil to the lens by either contracting or dilating in light or dark environment respectively. While in the camera, the DIAPHRAGM controls the amount of light entering the camera.

The PUPIL serves as the passage for light into the eye while in the camera, the APERTURE does the same.

The photosensitive surface in the eye is the YELLOW SPOT while in the camera, the photosensitive surface is the PHOTOGRAPHIC FILM.

5 0

2 years ago

A satellite of mass m orbits a moon of mass M in uniform circular motion with a constant tangential speed of v. The gravitationa

lukranit [14]

Answer:

Two stars, each of mass M, form a binary system. ... used is the distance between the centers of the planets; here that distance is 2R. ... r appears in the denominator of Newton's law of gravitation, the force of ... The orbital speed of a satellite orbiting the earth in a circular orbit at the ... is undergoing uniform circular motion?

Explanation:

Two stars, each of mass M, form a binary system. ... used is the distance between the centers of the planets; here that distance is 2R. ... r appears in the denominator of Newton's law of gravitation, the force of ... The orbital speed of a satellite orbiting the earth in a circular orbit at the ... is undergoing uniform circular motion?

3 0

2 years ago

Which metallloid has three valence electrons?

Naya [18.7K]

Boron Group
elements have three valence electrons and are fairly reactive. All of them are solids at room temperature. Boron is a very hard, black metalloid with a high melting point.

8 0

2 years ago

A 25kg chair initially at rest on a horizontal floor requires a 165 N horizontal force to set it in motion. Once the chair is in

SCORPION-xisa [38]

Answer:

$\mu_k=0.51$

Explanation:

Given that

Mass , m = 25 kg

We know that when body is in rest condition then static friction force act on the body and when body is in motion the kinetic friction force act on the body .That is why these two forces are given as follows

Static friction force ,fs= 165 N

Kinetic friction force ,fk = 127 N

If the body is moving with constant velocity ,it means that acceleration of that body is zero and all the forces are balanced.

Lets take coefficient of kinetic friction = μk

The kinetic friction is given as follows

fk = μk m g

Now by putting the values

127 = μk x 25 x 9.81

$\mu_k=\dfrac{127}{25\times 9.81}$

$\mu_k=0.51$

Therefore the value of coefficient of kinetic friction will be 0.51

4 0

2 years ago

In a thunder and lightning storm there is a rule of thumb that many people follow. After seeing the lightning, count seconds to

lubasha [3.4K]

Answer:

2.837% less than actual value.

Explanation:

Based on given information let's calculate our value.

S = Vxt = 331m/s x 5s = 1655m, that is the total distance that sound would travel in 5 seconds.

1mile = 1609.34meters.

percentage error is.

$\frac{actual-calculated}{actual} *100 = \frac{1609.34-1655}{1609.34} *100 = -2.83%$

negative indicates less than actual value.

3 0

3 years ago