If you found a new element how would you know it was new

Calculate the density of a substance with a volume 25 cm3 and mass 50 grams

Q - Explain the effect of Earth's gravity on objects on the surface of Earth. A - Gravity pulls objects toward Earth at a rate of 9.8 m/s2. Weight is the result of gravity's pull on a mass on Earth's surface.

Exercise and health

On a certain game show, contestants spin a wheel when it is their turn. One contestant gives the wheel an initial angular speed of 3.40 rad/s. The angular acceleration of the wheel is - 0.736 rad/s^2.

Isaac tosses a twig into a river to figure out how quickly the water is flowing. He observes that the twig travels 21 meters south in three seconds. Based on his observations, what is the velocity of the twig?

Light travels at 150000000km from the sun to earth in 8 minutes. What speed is this in Km/s

Electricity problem (coulomb's law)

An observer (O) spots a plane (P) taking off from a local airport and flying at a 29° angle horizontal to her line of sight and located directly above a tower (T). The observer also notices a bird (B) circling directly above her.

In order for convection to occur, you must have

Explain Newton's First Law for the following. If you walk across the room holding a ball, when should you drop it to ensure that it lands on a target? Before, after or when you are directly on the target?