Answer:
The mass of the object is 21 kg.
Step-by-step explanation:
To find the mass of an object with a given kinetic energy and velocity, you can use the formula for kinetic energy, which is KE = 1/2 * m * v^2, where m is the mass of the object, v is its velocity, and KE is its kinetic energy.
In your case, the velocity is 10 m/s and the kinetic energy is 105j, so you can solve for m by rearranging the formula to solve for mass.
This gives you m = 2 * KE / v^2, or m = 2 * 105j / 10^2, which means the mass of the object is 21 kg.