Define normal force in words

The normal force is the force that surfaces exert to prevent solid objects from passing through each other. If the object is at rest, the net force on the object is equal to zero. Therefore, the downward force (weight) must be equal to the upward force (normal force).

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

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