Question

A brick in the shape of a cube with sides 10 cm has a density of 2500 kg/m^3. What is its weight? a.) 250 N

b.) 2.5 N
c.) 25 N
d.) 0.001 N

Answer 1

c.) 25 N

Step-by-step explanation:

We find the volume of the brick, knowing that the volume of a cube is given by the formula:

`l=0,1 metros \\V=l^(3)\\V=(0,1\: \: m)^(3)=0,001\: \: m^(3)`

being l the side of the cube, which in this case is 10 cm or 0,1 m. Now we find the mass of the object, knowing the density and the Volume of the cube:

`m=V*d\\m=(0,001 \:\:m^(3))(2500 \: \: (Kg)/(m^(3)))=2,5 \:\: Kg`

We find the weight by multiplying the mass of the object with the gravity constant.

`W=m*g=(2.5 \:Kg)*(9,81 \:m/s^(2) )=24,5 N\approx25\: N`