What can you observe to know that when clear methane gas is burned it is a chemical change?

1) Change of color

2) Formation of a precipitate

3) Change in mass

4) Formation of a gas

5) Change in temperature

6) Change in shape

What is the wave speed of a sound wave if the frequency is 70 hertz and the wavelength is 0.4 meters

Identical cannon balls are fired with the same force, one each from four cannons having respective bore lengths of 1.0 meter, 2.0 meters, 2.5 meters and 3.0 meters.

You throw a ball upward from ground level with initial upward speed v0. What is the max height of the trajectory? How long does it take the ball to impact the ground? What is the speed of the ball when it hits the ground?

The moon appears to rise in the ___ and set in the ___ each day because the Earth rotates ___. Answers for the first 2 blanks: North, East, South, West Answers for the 3rd blank: Forward, Backward, Counterclockwise, Clockwise

An electric field around two charged objects is shown. What are the charges of objects X and Y?

A spring gains 2.34 joules of elastic potential energy as it is compressed 0.250 meter from its equilibrium position. What is the spring constant of this spring? (1) 9.36 N/m (3) 37.4 N/m (2) 18.7 N/m (4) 74.9 N/m

Form hypothesis: Where do you think we humans get energy?

The distance from home plate to the pitchers mound is 18.5 meters. For a pitcher capable of throwing at 3.85m/s (86mi/hr), how much time elapses between the release of the ball and the ball passing home plate?

A squirrel sitting on the ground starts to run with an acceleration of 5.1 m/s 2. How fast is the squirrel going after 0.25 seconds? A. 20.4 m/s B. 1.28 m/s C. 0.49 m/s D. 3.1 m/s

Describe how the competition between invasive and native species might affect a food web