To determine the child's mass given that the force of gravity acting on them is 490 newtons, we can use the formula for gravitational force:
[tex]\[ F = m \times g \][/tex]
Where:
- [tex]\( F \)[/tex] is the force of gravity (490 newtons),
- [tex]\( m \)[/tex] is the mass of the child (which we need to find),
- [tex]\( g \)[/tex] is the gravitational acceleration (approximated to 9.8 m/s[tex]\(^2\)[/tex] on Earth).
We can rearrange this formula to solve for the mass [tex]\( m \)[/tex]:
[tex]\[ m = \frac{F}{g} \][/tex]
Substituting the known values:
[tex]\[ m = \frac{490 \, \text{newtons}}{9.8 \, \text{m/s}^2} \][/tex]
When we perform the division, we get:
[tex]\[ m = 50 \, \text{kg} \][/tex]
So, the child's mass is [tex]\( 50 \, \text{kg} \)[/tex].
Therefore, the correct answer is:
C. 50 kg
