Answer:
[tex]\boxed {\boxed {\sf 243.75 \ J }}[/tex]
Explanation:
Kinetic energy is energy an object has due to motion. The formula is:
[tex]KE=\frac {1}{2}mv^2[/tex]
The mass of the object is 78 kilograms and the velocity is 2.5 meters per second.
[tex]m= 78 \ kg \\v= 2.5 \ m/s[/tex]
Substitute the values into the formula.
[tex]KE= \frac {1}{2} (78 \ kg)*(2.5 \ m/s)^2[/tex]
Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction. Solve the exponent first.
[tex]KE= \frac {1}{2}(78 \ kg)*6.25 \ m^2/s^2[/tex]
Multiply all three numbers together.
[tex]KE=39 \ kg * 6.25 \ m^2/s^2\\[/tex]
[tex]KE=243.75 \ kg*m^2/s^2[/tex]
1 kilogram meter squared per second squared is equal to 1 Joule. So, our answer of 243.75 kg *m²/s² is equal to 243.75 Joules.
[tex]KE=243.75 \ J[/tex]
The object has 243.75 Joules of kinetic energy.