As Myra needs to measure the gravitational force on the apple, a triple beam balance would be ideal to measure it.
The measure of the gravitational force on or near the Earth’s surface is its weight. This is the force of gravitation exerted by any object on Earth. Mass of an object determines its gravitational force. The force of gravitation or the measure of the weight is numerically equal to the product of mass of the object and the acceleration due to gravity on Earth which is constant having a value of 9.8 m/s^2.
