Question

1. a weight lifter does 420 j of work to lift a barbell a height of 0.35 m. what force did the weight lifter exert on the barbell?

Explanation:

Step1: Recall the work formula

The formula for work is \( W = F \cdot d \), where \( W \) is work, \( F \) is force, and \( d \) is distance. We need to solve for \( F \), so we can rearrange the formula to \( F=\frac{W}{d} \).

Step2: Substitute the given values

We know that \( W = 420\space J \) and \( d = 0.35\space m \). Substituting these values into the formula, we get \( F=\frac{420}{0.35} \).

Step3: Calculate the force

Calculating \( \frac{420}{0.35} \), we find that \( 420\div0.35 = 1200 \space N \).

Answer:

The force exerted by the weight lifter on the barbell is \( 1200\space N \).