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4 years ago

7

What are the advantages of using a telescope compared to making observations with the naked eye?

1 answer:

lara31 [8.8K]4 years ago

4 0

The naked eye is very limited. Unlike the telescope which can see far away.

You might be interested in

This type of electricity is produced when objects give up or gain electrons and

solniwko [45]

Answer: Static Electricity

6 0

3 years ago

An empty train car of mass 2.0 x 10^4 kg coasts along at 10 m/s. A 3000-kg boulder is suddenly dropped vertically into the car.

Zepler [3.9K]

Answer:8.69 m/s

Explanation:

Given

mass of Empty train $m=2\times 10^4 kg$

velocity of car $v=10 m/s$

mass of Boulder $M=3000 kg$

Since no External force is acting therefore conserving Momentum

Train and boulder moves with same velocity after collision

$m v=(M+m)v'$

$2\times 10^4\times 10=(2\times 10^4+3000)v'$

$v'=\frac{20,000\times 10}{23000}$

$v'=8.69 m/s$

8 0

3 years ago

24 POINTS!!!!!!!!!!!!

Karo-lina-s [1.5K]

Answer: Option (c) is the correct answer.

Explanation:

When the child is tossed up into the air then she gains kinetic energy as the child has moved from its initial position.

It is given that mass is 20 kg, velocity is $5 m/s^{2}$ , and height is 2 m.

Calculate the kinetic energy of child as follows.

kinetic energy = $\frac{1}{2}mv^{2}$

= $\frac{1}{2}20 kg \times (5 m/s)^{2}$

= $10 kg \times 25 m^{2}/s^{2}$

= $250 kg m^{2}/s^{2}$

Also, when child falls off the ground then she will have gravitational potential energy.

Calculate gravitational potential energy of child as follows.

Potential energy = m × g × h

= $20 kg \times 9.8 m/s^{2} \times 2 m$

= $392 kg m^{2}/s^{2}$

3 0

3 years ago

Read 2 more answers

Two long, parallel wires are attracted to each other by a force per unit length of 305 µN/m. One wire carries a current of 25.0

kykrilka [37]

To solve this problem we will use the concepts related to the electromagnetic force related to the bases founded by Coulumb, the mathematical expression is the following as a function of force per unit area:

$\frac{F}{L} = \frac{kl_1l_2}{d}$

Here,

F = Force

L = Length

k = Coulomb constant

I =Each current

d = Distance

Force of the wire one which is located along the line y to 0.47m is $305*10^{-6}N/m$ then we have

$l_2 = \frac{F}{L} (\frac{d}{kl_1})$

$l_2 = (305*10^{-6}N/m)(\frac{0.470m}{(2*10^{-7})(25A))})$

$l_2 = 28.67A$

Considering the B is zero at

$y = y_1$

$\frac{kI_2}{2\pi y} =\frac{kI_1}{2\pi y_1}$

$\frac{(4\pi*10^{-7})(28.67)}{2\pi (y_1)} = \frac{(4\pi *10^{-7})(25)}{2\pi (0.47-y_1)}$

$y_1 = 0.25m$

Therefore the value of y for the line in the plane of the two wires along which the total B is zero is 0.25m

5 0

4 years ago

The relationship between body mass body weight and body density

nordsb [41]

Answer:

The formula for calculating Density is:

= Mass / Volume

From this formula, we can say that the relationship between Mass and Density is a direct one. In other words, if mass is increasing - all else being equal - then density will increase as well.

If mass however was decreasing, density would have to decrease as well.

For example, assume 3 bricks have masses of 5kg, 10kg and 15kg. Also assume that the bricks all have the same volume of 5 m³.

Density of 5kg brick = 5 / 5 = 1 kg/m³

Density of 10kg brick = 10 / 5 = 2kg / m³

Density of 15kg brick = 15 / 5 = 3 kg /m³

<em>Notice how density increases as mass increases and decreases when mass decreases. </em>

7 0

3 years ago