Because the masses that you give are for blocks that are 1 cubic meter in volume, they also serve as the densities for the two metals that you are comparing.
<span>mass = density*volume </span>
<span>volume = (4/3)*pi*r^3 </span>
<span>volume of iron sphere = (4/3)*3.14*0.0201^3 = 3.40*10^-5 m^3 </span>
<span>mass of iron sphere = 7860* 3.40*10^-5 m^3 = 0.27 kg = mass of Aluminum Sphere </span>
<span>Volume of Al Sphere = 0.27/2700 = 9.90*10^-5 m^3 </span>
<span>Radius = cube root (volume / (4/3) / pi) = 2.87 cm. </span>
<span>I did this using the MS calculator, and I'm not 100% sure on the numerical answer, but the process is what you need to do to solve the problem. You should double check my answer.
hope this helped :)
</span>
B
Force=Mass times acceleration
15=3x
x=5ms^2
Answer:
13 m/s
Explanation:
I assume we are ignoring friction.
The boy's PE will all be converted to KE at the bottom of the hill.
to find PE = mgh we need to know h
h = 50 sin 10 = 8.68 meters
then: PE = 20 * 9.81 * 8.68 =<u> 1703.49</u> j
KE = 1/2 m v^2 = <u>1703 .49</u>
v = 13 m/s
