Please help me to solve the problem ?cm=1m

An object is placed 18 cm in front of spherical mirror.if the image is formed at 4cm to the right of the mirror, calculate it's

ivolga24 [154]

1) Focal length

We can find the focal length of the mirror by using the mirror equation:
$\frac{1}{f}= \frac{1}{d_o}+ \frac{1}{d_i}$ (1)
where
f is the focal length
$d_o$ is the distance of the object from the mirror
$d_i$ is the distance of the image from the mirror

In this case, $d_o = 18 cm$ , while $d_i=-4 cm$ (the distance of the image should be taken as negative, because the image is to the right (behind) of the mirror, so it is virtual). If we use these data inside (1), we find the focal length of the mirror:
$\frac{1}{f}= \frac{1}{18 cm}- \frac{1}{4 cm}=- \frac{7}{36 cm}$
from which we find
$f=- \frac{36}{7} cm=-5.1 cm$

2) The mirror is convex: in fact, for the sign convention, a concave mirror has positive focal length while a convex mirror has negative focal length. In this case, the focal length is negative, so the mirror is convex.

3) The image is virtual, because it is behind the mirror and in fact we have taken its distance from the mirror as negative.

4) The radius of curvature of a mirror is twice its focal length, so for the mirror in our problem the radius of curvature is:
$r=2f=2 \cdot 5.1 cm=10.2 cm$

3 0

3 years ago

A weather forecaster uses Doppler radar to predict the track of a storm near the town of hillville when the Doppler signal is he

Veseljchak [2.6K]

Answer: That the storm is moving toward hillville and that residents should be prepared.

Explanation:

6 0

3 years ago

1. What do you mean by energy ?

sammy [17]

Answer:

1. The ability of a body to do a work is called energy.

2. The S.I. unit of energy is joule(J).

3.The different types of energy are :

Mechanical Energy
Heat Energy
Light Energy
Sount Energy
Electrical Energy
Magnetic Energy
Chemical Energy
Nuclear Energy

Explanation:

<h3 /><h3>Hope it works out !!</h3>

5 0

3 years ago

What was anton van leeuwenhoek famous for

monitta

Answer:

He is known as the first microbiologist and also “the Father of Microbiology” because he was the first to observe bacteria underneath a microscope. He made many other significant discoveries in the field of biology and also made important changes to the microscope.

Explanation:

hope this helps. and if it did pls mark brainliest :)

3 0

3 years ago

The electric motor of a model train accelerates the train from rest to 0.620 m/s in 21ms. The total mass of the train is 825 g.

Rudiy27

Explanation:

Average power = change in energy / change in time

P = ΔE / Δt

P = (½ mv²) / t

P = (½ (0.825 kg) (0.620 m/s)²) / (0.021 s)

P = 7.55 Watts

7 0

3 years ago

Please help me to solve the problem?cm=1m​

Please help me to solve the problem?cm=1m