According to my examination I have confirmed that I do NOT repeat do NOT know this .
私は英語がわかりません sorry pls translate
Answer:
Force = 2802.8 Newton
Explanation:
Given the following data;
Mass = 130 lbs
But, 2.2 lbs = 1.0 kg
130 lbs to kg = 130 * 2.2 = 286 kg
Acceleration due to gravity = 9.8m/s²
To find the force in Newton;
Force = mass * acceleration due to gravity
Force = 286 * 9.8
Force = 2802.8 Newton
Assuming all the substances are already at the temperature that is their melting point, we only need to worry about the heat required to change state, not the heat required to change temperature.
No calculations necessary for this question - just look at the latent heat of fusion. The higher this value, the more heat required per unit mass of the substance to melt it. Of the four answer options, aluminum has the highest value and therefore will take the most heat to melt the same mass.
Here are two ways to do it:
<u>Way #1:</u>
-- You know that gravity accelerates things that are falling freely, adding 9.8 m/s to their speed every second.
-- After 6 seconds, an object that fell from rest winds up falling at (9.8 x 6) = 58.8m/s.
-- During that time, its average speed was 1/2(0 + 58.8) = 29.4 m/s .
-- In 6 seconds, at an average speed of 29.4 m/s, it covers (29.4 x 6) = <em>176.4meters</em>.
<u>Way #2:</u>
This way only works if you remember the formula for the distance covered during uniform acceleration.
D = 1/2 (acceleration) (time)²
Acceleration = gravity = 9.8 m/s²
Time = 6 seconds
D = 1/2 (9.8) (6)² = <em>176.4 meters</em>.
