FORMULAS:Potential Energy:PE= mghKinetic Energy:KE = ½ mv²1. A mass of 2 kg. is taken from the ground to the height of10m. Find the potential energy of the object.2. What is the kinetic energy with a mass of 200 kg movingat 5 m/s?
Answer (1)
1. SOLUTION:Step 1: List the given values.[tex]\begin{aligned} & m = \text{2 kg} \\ & h = \text{10 m} \end{aligned}[/tex]Step 2: Calculate the potential energy.[tex]\begin{aligned} PE & = mgh \\ & = (\text{2 kg})(\text{9.8 m/s}^2)(\text{10 m}) \\ & = \boxed{\text{196 J}} \end{aligned}[/tex]Hence, the potential energy gained of the object is 196 J.2. SOLUTION:Step 1: List the given values.[tex]\begin{aligned} & m = \text{200 kg} \\ & v = \text{5 m/s} \end{aligned}[/tex]Step 2: Calculate the kinetic energy.[tex]\begin{aligned} KE & = \frac{1}{2}mv^2 \\ & = \frac{1}{2}(\text{200 kg})(\text{5 m/s})^2 \\ & = \boxed{\text{2,500 J}} \end{aligned}[/tex]Hence, the kinetic energy is 2,500 J.
