All categories

3 years ago

We can see our face clearly on mirror why cant we see our face clear on aluminium or irion plate

Physics

1 answer:

Simora [160]3 years ago

8 0

Because specular reflection occurs with a mirror, while diffuse reflection occurs with aluminium or iron plate

Explanation:

Reflection is a phenomenon typical of waves (such as light wave), that occurs when a wave bounces off the surface of a certain material, going back into the original medium at a certain angle, without changing speed, frequency or wavelength.

The direction of the reflected ray is given by the law of reflection, which states that:

The incoming ray, the reflected ray and the normal to the surface all lie on the same plane
The angle of incidence is equal to the angle of reflection

Depending on the type of surface, two different types of reflection can occur:

Specular reflection: this occurs when the surface is perfectly smooth. In such a case, all the incoming rays of light hit the surface with same angle of incidence, therefore they are reflected at the same angle. This means that a perfect and clear image of the original object can be formed: this is the case of a mirror.
Diffuse reflection: when the surface is not smooth, the imperfections on the surface are such that the incoming rays of light hit the surface at different angles of incidence. As a result, the rays are reflected at different angles to each other, and therefore no clear image of the object is produced. This is the case of aluminium or iron plate.

Learn more about reflection and other wave phenomena:

brainly.com/question/3183125

brainly.com/question/12370040

#LearnwithBrainly

You might be interested in

Plastic and glass rods that have been charged by rubbing with wool and silk, respectively, hang by threads.

nikitadnepr [17]

Answer:

a. The object will attract the glass rod.

b. The object will repel the glass rod.

Explanation:

a. When you rub a plastic rod with wool, it becomes negatively charged. This is because the wool material loses some of its electrons to the plastic rod. The wool becomes positively charged while the plastic rod becomes negatively charged.

Hence, for an object to repel the negatively charged plastic rod, it must also be negatively charged. This is because objects with like charges repel one another.

On the other hand, when you rub a glass rod with a silk material, it becomes positively charged. This is because the glass rod loses its electrons to the silk material. The silk material then becomes negatively charged, while the glass rod becomes positively charged.

Therefore, the negatively charged object will attract the already positively charged glass rod.

b. For an object to attract a negatively charged plastic rod, then it must be positively charged, since unlike charges attract.

So, a positively charged object will repel the negatively charged glass rod.

7 0

3 years ago

A 0.439 kg puck, initially at rest on a horizontal, frictionless surface, is struck by a 0.307 kg puck moving initially along th

lesya [120]

Answer:

u2 = 0.266 m/s

Explanation:

Let the left Puck mass at rest = m1 =0.307 Kg

mass of the right puck m2 = 0.439 kg

velocity of m1 before collision v1= 2.19 m/s

velocity of m2 before collision v2 = 0m/s

velocity of m1 after collision u1 =1.19 m/s

velocity of m2 after collision u2 = ? m/s

θ = 37°

<u>Solution:</u>

Before collision:

Momentum (y-axis ) before collision= 0 Kgm/s

Momentum (x-axis ) before collision= m1v1 + m2v2 = 0.307 Kg x 2.19 m/s + 0

= 0.672 Kgm/s

After collision:

Momentum (y-axis ) after collision= m1u1 sinθ + m2u2 sinθ

= 0.307 x 1.19 m/s sin 37 ° + 0.439 x u2 sin 37°

= 0.22 + 0.26 u2

Momentum (x-axis ) after collision= m1u1 cosθ + m2u2 cos θ

= 0.307 x 1.19 m/s cos 37 ° + 0.439 x u2 cos 37°

= 0.29 + 0.35 u2

According to law of conservation momentum

momentum before collision = momentum after collision.

0 + 0.672 Kgm/s = 0.22 Kgm/s + 0.26 kg u2 + 0.29 Kgm/s + 0.35 kg u2

0.672 Kgm/s = 0.51 Kgm/s + 0.61 u2

u2 = 0.266 m/s

6 0

4 years ago

A 480N sphere 40.0cm in radius rolls without slipping 1200cm down a ramp that is inclined at 53 0 with the horizontal. What is t

IgorC [24]

As we know that sphere roll without slipping so there is no loss of energy in this case

so here we can say that total energy is conserved

Initial Kinetic energy + initial potential energy = final kinetic energy + final potential energy

$\frac{1}{2}mv_i^2 + mgh = \frac{1}{2}mv^2 + \frac{1}{2}I\omega^2+ mgh'$

as we know that ball start from rest

$v_i = 0$

height of the ball initially is given as

$h = Lsin\theta$

$h = 1200sin53 = 960 cm$

also we know that

$I = \frac{2}{5}mR^2$

also for pure rolling

$v = r\omega$

also we know that

$480 = m*9.8$

$m = 49 kg$

now plug in all data in above equation

$480*9.60 + 0 = \frac{1}{2}*49*(0.40*\omega)^2 + \frac{1}{2}*\frac{2}{5}*49*(0.40)^2\omega^2 + 0$

$4608 = 3.92\omega^2 + 1.568\omega^2$

$\omega^2 = 839.65$

$\omega = 29 rad/s$

So speed at the bottom of the inclined plane will be 29 rad/s

7 0

4 years ago

Gravity causes___ objects to accelerate

kolbaska11 [484]

Gravity causes falling objects to accelerate.

4 0

4 years ago

Read 2 more answers

Three students are having a conversation. It goes like this. Allison says: "This problem says, can you add a resistor to the cir

notsponge [240]

Answer:

Nima and Natasha are absolutely correct.

Explanation:

When connecting two resistors in series, their resistances add:

$R_{eq}=R_{1}+R_{2}$

which means that whenever we add a resistance in series, their magnitudes will add, giving us a resistance that is greater than the original resistance, which will demand less current from the battery because of ohm's law:

$I=\frac{V}{R}$

So, the greater the resistance, the smaller the current.

When connecting two resistors in parallel, the reciprocal of ther resistances add:

$\frac{1}{R_{eq}}=\frac{1}{R_{1}}+\frac{1}{R_{2}}$

$R_{eq}=\frac{R_{1}R_{2}}{R_{1}+R_{2}}$

The equivalent resistance will always be less than the smallest resistor in the circuit, so the equivalent resistance will always decrease as more resistors are added. A decrease in the resistance means that the current will increase.

8 0

3 years ago