Explanation:
For each object, the initial potential energy is converted to rotational energy and translational energy:
PE = RE + KE
mgh = ½ Iω² + ½ mv²
For the marble (a solid sphere), I = ⅖ mr².
For the basketball (a hollow sphere), I = ⅔ mr².
For the manhole cover (a solid cylinder), I = ½ mr².
For the wedding ring (a hollow cylinder), I = mr².
If we say k is the coefficient in each case:
mgh = ½ (kmr²) ω² + ½ mv²
For rolling without slipping, ωr = v:
mgh = ½ kmv² + ½ mv²
gh = ½ kv² + ½ v²
2gh = (k + 1) v²
v² = 2gh / (k + 1)
The smaller the value of k, the higher the velocity. Therefore:
marble > manhole cover > basketball > wedding ring
We know the formula for density = Mass/ volume
So Mass, M = Volume * Density
Volume = 3.5 L= 0.0035
Density = 1.50 g/ml = 1500 
Mass, M = 0.0035*1500 = 5.25 kg
So mass of liquid having density 1.50 g/ml and volume 3.5 liters is 5.25 kg.
Answer:
0.2448 point²
Explanation:
1 gry = 1/10 line
1 line = 1/12 inch
=> 1 gry in inches = 1/10 * 1/12 = 1/120 inch
=> 1 inch = 120 gry
1 point = 1/72 inch
=> 1 inch = 72 points
Therefore,
120 gry = 72 points
=> 1 gry = 3/5 point
Therefore,
1 gry² = (3/5)² point²
1 gry² = 9/25 point²
This means that 0.68 gry² will be:
0.68 gry² = 0.68 * 9/25 point²
=> 0.68 gry² = 0.2448 point²