If the half - life of a sample of a radioactive substance is 30 seconds, how much would be left after 60 seconds?

What is the pressure from made from a book with the dimensions of 47 cm * 86 cm and a measured force of 900N?

The horsepower (hp) that a shaft can safely transmit varies jointly with its speed (in revolutions per minute, rpm) and the cube of its diameter.

Two vectors are presented as a=3.0i + 5.0j and b=2.0i+4.0j find (a) a x b, ab (c) (a+b) b and (d) the component of a along the direction of b.

How is work affected when an object is lifted straight up instead of using a ramp? A) Work will increase. B) Work will decrease. C) Work will stay the same. D) Work will depend on mass of the object.

A 160.0 km long electric power line made out of copper is installed during the Spring months at an average temperature of 10.2 °C. 1) What is the change in the length of the power line on a hot summer day, when the temperature is 32.

A group of scientists is trying to launch an object into orbit, and the object is traveling at 6500 m/s. Which best explains why the object will not successfully orbit Earth? A.) There is not enough air resistance to keep the object moving. B.

Why is a coin able to float on top of water in a glass

Here we will look at a more complex problem for which we will use all three of our primary constant acceleration equations. a motorcyclist heading east through a small iowa town accelerates after he passes a signpost at x=0 marking the city limits.

Drag each tile to the correct box. Arrange the objects in order from least to greatest potential energy. Assume that gravity is constant. (Use PE = m * g * h.) 1.) a 15-kilogram stone found at a height of 3 meters 2.

On a cold winters da, y, If you left a drink setting outside, it could freeze. Explain why in a complete sentence Hint-Consider th kinetic theory of heat that explains that temperature is directly related to kinetic energy of atoms.