Respuesta :

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.

  • (2.5 m/s)²= 2.5 m/s * 2.5 m/s = 6.25 m²/s²

[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.