An iron weight, suspended by a string, is motionless. The tension in the string is 4.75 newtons. What is the mass of the iron
weight?

Explanation:

If the mass hangs at the end of the string and the string can support the mass and doesn't break, and the mass hangs still, that means that the tension in the string is equal to the downward pull of the mass. However, we are given the tension in Newtons and the mass needs to be in kg. So we use the equation for weight:

w = mg where w, the weight, is the same as the tension in the string. Gravity is always 9.8 in the metric system:

4.75 = m(9.8) so

m = .48 kg

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2