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3 years ago

What does the blackboard do when white light falls on it?

1 answer:

5 0

Actually a black board has all colours in light or white light . So when light falls on it board absorbs all colours because all are present so no light is reflected back. That is the case, and so it will appear black as it absorbs all colours of light that fall on it .

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Which diagram correctly represents the electric field lines between two small electrically charged spheres?

hjlf

Answer:

hehe

Explanation:

6 0

3 years ago

2. Fill in the blanks

slamgirl [31]

Answer:

a. Two bodies are rubbed against each other they acquire equal and Opposite charge.

b. Electron are transferred from one object to another when two objects are charged by friction.

c. Lightening rod is a device used to secure tall buildings from the effect of lightning

d. Negative charge is obtained by plastic comb when rubbed with dry hair.

e. Lightning is natural spark discharge on huge scale.

Hope this helps you. Do mark me as brainliest.

4 0

3 years ago

On a straight horizontal track along which blocks can slide with negligible friction, block 1 slides toward block 2, which is in

vivado [14]

If the mass and post-collision speed of block 1 is known, the momentum of the block 2 can be determined.

<h3>What is momentum?</h3>

The momentum of an object in motion is the product of mass and speed of the object.

P = mv

<h3>Conservation of linear momentum</h3>

The principle of conservation of linear momentum states that, the sum of the initial momentum must be equal to the sum of the final momentum.

$m_1v_1 = m_2 v_2$

Thus, if the mass and post-collision speed of block 1 is known, the momentum of the block 2 can be determined.

Learn more about conservation of linear momentum here: brainly.com/question/7538238

7 0

2 years ago

Janet jumps horizontally off a high diving platform with a velocity of 2.63 m/s and lands in the water 1.9 s later. How high is

soldier1979 [14.2K]

Answer:

The height of the platform is 22.686 m.

Explanation:

Given;

initial velocity of Janet, u = 2.63 m/s

time of her motion, t = 1.9 s

The height of the platform is given by;

h = ut + ¹/₂gt²

substitute the given values and solve for height "h"

h = (2.63 x 1.9) + ¹/₂(9.8)(1.9)²

h = 4.997 + 17.689

h = 22.686 m

Therefore, the height of the platform is 22.686 m.

5 0

4 years ago

A truck is moving at 25.0 m/s and sees a barrier in the road 100 m ahead. The truck can decelerate at 4 m/s2. Will the truck hit

Nimfa-mama [501]

Answer:

No, the truck will not cross the barrier.

The closeness of the truck to the barrier is of 21.875 m

Solution:

As per the question:

Velocity of the truck, v = 25.0 m/s

Acceleration of the truck, a = - 4 $m/s^{2}$

Now,

Since, the barrier at a distance of 100 m. Thus in order to check whether the truck hit the barrier or not, we will see the distance, d it covers by using the kinematic eqn:

$v'^{2} = v^{2} + 2ad$