Tiffany leaves several balloons filled with helium gas inside her car on a sunny day. When she returns to her car, some of the balloons are much larger and a few have popped. Explain what happened.

In a phasor representation of a transverse wave on a string, what does the length of the phasor represent?

Suppose all the grains in a sample of sand were exactly the same size. Could the sample still be a heterogeneous mixture?

A box of groceries requires 5.0 newtons of force to lift it up 1.0 meter. How much work is done?

If a positively charged particle moves into a magnetic field traveling in a straight line, how would you expect it's motion to change

If all of the forces acting on an object balance so that the net force is zero, then (A) the object must be at rest (B) the object's speed will decrease (C) the object will follow a parabolic trajectory (D) the object's direction of motion can

As part of his meal, a workman has a cup containing a hot drink. In order to keep the drink hot whilst he eats the rest of his meal, he covers the cup, as shown in the figure. Which sources of energy loss does this action reduce? Tick two boxes.

When energy is transformed, the amount of usable energy?

If an object weighs 39.2 n on earth, what is its mass

What happens when pressure is applied to a solid.

A box of mass 1 kg is hung from a spring scale. The reading on the spring scale is approximately 10N. What would be the reading on the spring scale if a box of mass 5 kg is hung from it? (Assume acceleration due to gravity to be 10 m/s2.