There is a 10 cm long cube with a mass of 7.8 kg, which is placed on the table with an area of 1 square meter (1) What is the density of the block? (2) what is the pressure of the block on the desktop? (3) what is the pressure of the block on the desktop?

There is a 10 cm long cube with a mass of 7.8 kg, which is placed on the table with an area of 1 square meter (1) What is the density of the block? (2) what is the pressure of the block on the desktop? (3) what is the pressure of the block on the desktop?


1. V = (10 cm) to the third power = (10 to the third power) M & # 179;
Density = m / v = 7.8kg / (the third power of 10) M & # 179; = (the third power of 7.8 * 10) kg / M & # 179;
2、F=mg=7.8kg*10N/kg=78N
3. S = (10cm) & # 178; = 10 of - 2M2
P = f / S = 78n / (the - 2 power of 10) m2 = 7800pa