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3 years ago

If a magnet is attracted to a metal object what can you say about the pole of the magnet and the pole of a object ?

1 answer:

7 0

Space surrounding magnet is called the magnetic field. In this field we can encounter magnetic force. Magnet attraction occurs when poles are unlike and is caused by magnetic force. It means that poles should have opposite values.

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What nutrient is easiest to be broken down and absorb energy ?

Dahasolnce [82]

Carbohydrates. Especially simple starches like white bread

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3 years ago

Read 2 more answers

If a wave has a frequency of 50 Hz and a wavelength of 2 meters.<br> Find its speed.

natka813 [3]

Answer:

100 m/s

Explanation:

here we use the wave equation which states that the velocity is equal to the product of the frequency and the wavelength.

so v = 50 × 2

v = 100 m/s

6 0

3 years ago

A protostar's radius decreases by a factor of 100 and its surface temperature increases by a factor of two before it becomes a m

Sliva [168]

Answer:

$L_f = K (\frac{r}{100})^2 * (2T)^4$

$L_f = K \frac{r^2}{10000} * 16 T^4$

$L_f = \frac{16}{10000} k r^2 T^4 = \frac{1}{625} k r^2 T^4$

$L_f = \frac{1}{625} L_i$

So then we see that the final luminosity decrease by a factor of 625 so then the correct answer for this case would be:

B. Decreases by a factor of 625

Explanation:

For this case we can use the formula of luminosity in terms of the radius and the temperature given by:

$L_i = K r^2 T^4$

Where L_i = initial luminosity, r= radius and T = temperature.

We know that we decrease the radius by a factor of 100 and the temperature increases by a factor of 2 so then the new luminosity would be:

$L_f = K (\frac{r}{100})^2 * (2T)^4$

$L_f = K \frac{r^2}{10000} * 16 T^4$

$L_f = \frac{16}{10000} k r^2 T^4 = \frac{1}{625} k r^2 T^4$

$L_f = \frac{1}{625} L_i$

So then we see that the final luminosity decrease by a factor of 625 so then the correct answer for this case would be:

B. Decreases by a factor of 625

6 0

3 years ago

A spring that has a force constant of 1050 N/m is mounted vertically on the ground. A block of mass 1.95 kg is dropped from rest

aleksandrvk [35]

Answer:

25.2 cm

Explanation:

K = 1050 N/m

m = 1.95 kg

h = 1.75 m

By the conservation of energy, the potential energy of the block is converted into the potential energy stored in the spring

m g h = 1/2 x k x y^2

Where, y be the distance by which the spring is compressed.

1.95 x 9.8 x 1.75 = 1/2 x 1050 x y^2

33.44 = 525 x y^2

y = 0.252 m

y = 25.2 cm

8 0

3 years ago

A 6.0-kg object moving at 5.0 m/s collides with and sticks to a 2.0-kg object. After the collision the composite object is movin

gogolik [260]

Answer:

a) 23 m/s

Explanation:

Assuming no external forces acting during the collision, total momentum must be conserved, as follows:

$p_{o} = p_{f} (1)$

The initial momentum p₀, can be written as follows:

$p_{o} = m_{1} * v_{1o} + m_{2}* v_{2o} = 6.0 kg * 5.0 m/s + 2.0 kg * v_{2o} (2)$

The final momentum pf, can be written as follows:

$p_{f} = (m_{1} + m_{2} )* v_{f} = 8.0 kg* (-2.0 m/s) (3)$

Since (2) and (3) are equal each other, we can solve for the only unknown that remains, v₂₀, as follows:

$v_{2o} = \frac{-6.0kg* 5m/s -8.0 kg*2.0m/s}{2.0kg} = \frac{-46kg*m/s}{2.0kg} = -23.0 m/s (4)$

This means that the 2.0-kg object was moving at 23 m/s in a direction opposite to the 6.0-kg object, so its initial speed, before the collision, was 23.0 m/s.

6 0

3 years ago