A teacher stands well back from an outside doorway 0.88 m wide, and blows a whistle of frequency 780 Hz. Ignoring reflections, estimate at what angle (s) it is not possible to hear the whistle clearly on the playground outside the doorway.

Ancient Greek philosophers spent lots of time thinking about science and imaging explanations for the natural world. What part of the scientific process did they need to do A. Testing B. Creative thinking C. Debate D. Argumentation

What is the name of a particle with no charge in an atom?

Which of the following causes a current in an electrical circuit? A. resistance B. a current difference C. a voltage difference D. the shape of the electrical circuit

Which fact is NOT true about gravity? Gravity depends on distance. Gravity depends on weight. The force of gravity between two objects will never be 0. Gravity depends on mass.

In a process called pair production, an energetic gamma ray is converted into an electron and a positron.

A Blu-ray disc is approximately 11 centimeters in diameter. The drive motor of a Blu-ray player is able to rotate up to 10,000 revolutions per minute. (a) Find the maximum angular speed (in radians per second) of a Blu-ray disc as it rotates

A body has translatory motion if it moves along a

What is Nothing. (sorry i have been wondering this for a very long time)

What is the weight of a 15kg dog on earth?

Identify the scenario below as to whether they increase, decrease, or not change the frequency in which a string vibrates and thus change its pitch. Assume that no other changes are happening. 1. Tightening a string for greater tension 2.