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4 years ago

In what scenario might a red ball appear black?

Physics

1 answer:

zhuklara [117]4 years ago

3 0

A scenario a red ball might appear black is when there is a shadow in front of it.or when the ball is in a dark place.

You might be interested in

What happens to the size of atoms as we go from left to right on the periodic table? T

Lady_Fox [76]

Answer:

Atomic size gradually decreases from left to right across a period of elements.

Explanation:

This is because, within a period or family of elements, all electrons are added to the same shell. However, at the same time, protons are being added to the nucleus, making it more positively charged.

8 0

3 years ago

On a speed-time graph, a horizontal line shows the change in speed is ____.

spayn [35]

On a speed/time graph, the height of the line at any point
shows the speed at that moment. If the line is horizontal,
then its height isn't changing, meaning that the speed isn't
changing. It's constant. The change is zero, until the line
starts rising or falling.

4 0

4 years ago

II) One 3.2-kg paint bucket is hanging by a massless cord from another 3.2-kg paint bucket, also hanging by a massless cord, as

Greeley [361]

Answer:

Here , mass of bucket ,m = 3.2 Kg

Now , let the tension in upper rope is T1

the tension in the middle rope is T2

For lower bucket, balancing forces in vertical direction

T2 - mg = 0

T2 = mg

T2 = 3.2 *9.8

T2 = 31.36 N

tension in the middle rope is 31.36 N

For the upper bucket , balancing forces in vertical direction

T1 - T2 - mg = 0

T1 = T2 + 3.2 *9.8

T1 = 62.72 N

the tension in the upper rope is 62.72 N

for a = 1.25 m/s^2

Using second law of motion ,for both the buckets

Fnet = ma

T1 - 2mg = 2m*a

T1 = 2*3.2*(9.8 +1.25)

T1 = 70.72 N

the tension in the upper rope is 70.7 N

Now , the lower bucket

Using second law of motion,

T2 - mg = ma

T2 = 3.2 * (9.8 + 1.25)

T2 = 35.36 N

the tension in the lower rope is 35.36 N

7 0

3 years ago

Is an object in a free fall when no force but gravity acts on it?

aleksklad [387]

I'm pretty sure that's exactly the formal definition of 'free fall'.

5 0

4 years ago

A soccer coach riding his bike reaches his office in xx hours. If he travels at 24 km/h, he reaches his office 5 minutes late. I

Elina [12.6K]

Answer:

18 km

Explanation:

Let 'd' be the distance between his house and office.

Normal time taken to reach the office = 'x' hours.

If speed is 24 km/h, time is increased by 5 minutes.

If speed is 30 km/h, time is reduced by 4 minutes.

We know that,

Time taken = Distance traveled ÷ Speed

So, when speed is 24 km/hr, time is increased by 5 minutes.

$1\ min = \frac{1}{60}\ h\\5\ min =\frac{5}{60}=\frac{1}{12}\ h$

So, time is $x+\frac{1}{12}$

Therefore,

$x+\frac{1}{12}=\frac{d}{24}\\\\x=\frac{d}{24}-\frac{1}{12}\\\\x=\frac{1}{12}(\frac{d}{2}-1)---------1$

Now, when speed is 30 km/h, time is reduced by 4 minutes or $\frac{4}{60}=\frac{1}{15}\ hours$

So, time now is $x-\frac{1}{15}$

Again using the time formula, we have

$x-\frac{1}{15}=\frac{d}{30}\\\\x=\frac{d}{30}+\frac{1}{15}\\\\x=\frac{1}{15}(\frac{d}{2}+1)-------------2$

Equations (1) and (2) are equal. So,

$\frac{1}{12}(\frac{d}{2}-1)=\frac{1}{15}(\frac{d}{2}+1)\\\\\frac{15}{12}(\frac{d}{2}-1)=\frac{d}{2}+1\\\\\frac{5d}{8}-\frac{5}{4}=\frac{d}{2}+1\\\\\frac{5d}{8}-\frac{d}{2}=1+\frac{5}{4}\\\\\frac{5d-4d}{8}=\frac{4+5}{4}\\\\\frac{d}{8}=\frac{9}{4}\\\\d=\frac{9\times 8}{4}=\frac{72}{4}=18\ km$

Therefore, the office is 18 km from his house.

6 0

3 years ago