Answer:
C
Explanation:
During an investigation you want to investigate different variables.
The kinetic energy of the child at the bottom of the incline is 106.62 J.
The given parameters:
- <em>Mass of the child, m = 16 kg</em>
- <em>Length of the incline, L = 2 m</em>
- <em>Angle of inclination, θ = 20⁰</em>
The vertical height of fall of the child from the top of the incline is calculated as;

The gravitational potential energy of the child at the top of the incline is calculated as;

Thus, based on the principle of conservation of mechanical energy, the kinetic energy of the child at the bottom of the incline is 106.62 J since no energy is lost to friction.
Learn more about conservation of mechanical energy here: brainly.com/question/332163
Answer:
357.6g
Explanation:
Given parameters:
Density = 12.459g/cm³
Volume of metal = 28.7cm³
Unknown:
Mass of metal = ?
Solution:
The density of a substance is its mass per unit volume.
To find the mass;
Mass of metal = density x volume
Now insert the parameters and solve;
Mass of metal = 12.459 x 28.7 = 357.6g
5-14 m/s in 3 seconds
a=vf-vi/t
a=14-5/3
a=9/3
a=3 m/s^2