Why do elements need to be heated to emit color?

How much work will it take to lift a 2-kg pair of hiking boots 2 meters off the ground and onto a shelf in your closet? O A. 2.45 J OB. 4J C. 39.2 J D. 20 J

If a ball is thrown off of a 123 m cliff at a speed of 18 m/s, how far from the base of the cliff is the ball?

Consider an electrical transformer has 10 loops on its primary coil and 20 loops on its secondary coil. What is the voltage in the secondary coil if the primary coil is supplied with 120 V?

Which occupation is not an example of specialization? A waiter B journalist C student OD carpenter

A force that opposes motion between surfaces that are touching

An exhausted bicyclist pedals somewhat erratically when exercising on a static bicycle. The angular velocity of the wheels follows the equation? (t) = at? bsin (ct) fort?0, where t represents time (measured in seconds), a = 0.500 rad/s2, b = 0.

This boy uses a force to lift a heavy rock. (He is carrying it.) What can the boy do if he wants to lift the same rock more quickly? A. use greater upward force B. use greater downward force C. decrease the force of gravity D.

The difference in electronegativity values between H and O is 1.4. What type of bond will these elements form?

True or false. when light passes from one medium to another the speed changes.

Examples of a scalar