All categories

3 years ago

A 40 kg boy on a skateboard throws a 2 kg ball at 20 m/s to the left. How fast did the boy move to the right on his skateboard?

Physics

1 answer:

sergey [27]3 years ago

4 0

According to my examination I have confirmed that I do NOT repeat do NOT know this .

You might be interested in

A watt is a unit of light power force motion energy

Crazy boy [7]

The answer would be Power

3 0

3 years ago

The box plots show the summer temperatures, in degrees Fahrenheit, in two cities. Summer Temperatures in City A Summer Temperatu

Inga [223]

Answer:b

Explanation:

7 0

4 years ago

Read 2 more answers

Identify the origins of breakdown when using a spectrum analyzer

Zanzabum

Four regions of the electromagnetic spectrum that astronomers use when observing objects in the space are the following enumerated answers.

1. First is Ultraviolet

2. Next is Infrared

3. Then the radio

4. Lastly the Visible lights.

These are the answers to the problem.

7 0

3 years ago

How do the different forms of potential energy depend on an object's position or chemical composition?

devlian [24]

It depends on the objects chemical composition.

6 0

3 years ago

find the time taken, if the speed of a train increased from 72 km/hr to 90 km/hr for 234 km. leave your answer in seconds

Airida [17]

Answer:

Time taken = 10400 s

Explanation:

Given:

Initial speed of the train, $u=72\textrm{ km/h}=72\times \frac{5}{18}=20\textrm{ m/s}$

Final speed of the train, $v=90\textrm{ km/h}=90\times \frac{5}{18}=25\textrm{ m/s}$

Displacement of the train, $S=234\textrm{ km}=234\times 1000=234000\textrm{ m}$

Using Newton's equation of motion,

$v - u = at\\a=\frac{v-u}{t}$

Now, using Newton's equation of motion for displacement,

$v^{2}-u^{2}=2aS$

Now, plug in the value of $a=\frac{v-u}{t}$ in the above equation. This gives,

$v^{2}-u^{2}=2\times \frac{v-u}{t}\times S\\(v+u)(v-u)=\frac{2(v-u)S}{t}\\t=\frac{2(v-u)S}{(v+u)(v-u)}\\t=\frac{2S}{v+u}$

Now, plug in 234000 m for $S$ , 25 m/s for $v$ and 20 m/s for $u$ . Solve for $t$ .

$t=\frac{2S}{v+u}\\t=\frac{2\times 234000}{25+20}\\t=\frac{468000}{45}=10400\textrm{ s}$

Therefore, the time taken by the train is 10400 s.

3 0

4 years ago