Interactions

In a garden food web, if the population of birds (predators) suddenly decreases, what is the most likely immediate effect on the caterpillars (prey)?

The photograph shows a metal spring being stretched. Wei Ming keeps adding heavier and heavier weights to the spring. He observes that at first the extension increases steadily with each added weight, but after a certain point the spring becomes permanently longer and no longer returns to its original length when the weights are removed. Which BEST explains what has happened?

Jia Yi dropped a ball from the top of a building. Which of the following is true about the gravitational force acting on the ball as it falls?

A spring balance is used to measure the weight of an object. Which property of the spring is being utilized?

Daniel is trying to push a heavy crate across the floor. Which of the following would make it EASIER for him to move the crate?