Junior High School Ultimate Science Reviewer and Practice Quizbook

1. 1Chapter 1: Biology - Cell Biology and Ecosystem DynamicsComprehensive review of cell structures, cellular processes, energy transfer in ecosystems, and biodiversity.

A force is a push or a pull acting upon an object as a result of its interaction with another object. When forces are balanced, the net force is zero, and the motion of the object does not change. When forces are unbalanced, a net force acts on the object, causing it to accelerate in the direction of the net force. Key Formula: Newton's Second Law of Motion states that Force equals mass times acceleration (F = m × a). If a 2 kg object experiences an acceleration of 3 m/s², the net force acting on it is 6 Newtons.

1. 1Question 1A cart with a mass of 10 kg is pushed with a net force of 50 N. What is the acceleration of the cart? A) 0.2 m/s² B) 5 m/s² C) 500 m/s² D) 50 m/s² Answer: B) 5 m/s² Explanation: Using Newton's Second Law (a = F / m), divide the net force (50 N) by the mass (10 kg), resulting in 5 m/s².