A girl with mass of 40 kg sits on a sled at rest with a man of 15 kg. What is the kinetic energy of the girl and sled together

4. What information does the atomic number of an element give us?

A bolt falls off an airplane high above the ground. How far does the bolt have to fall before its speed reaches 100m/s (about 200 miles per hour) ? You should ignore air friction in your calculation.

Water is sold on half-liter bottles. What is the mass, in kg and in g, of the water in such a full bottle?

What techniques allow us to identify the presence of different elements?

A 12-V battery is connected to a device and 24 mA (24 x 10' Amps) of current flows through it. If the device obeys Ohm's law, how much current will flow when a 24-V battery is used?

A sound from a source has an intensity of 270 db when it is 1 m from the source. what is the intensity of the sound when it is 3 m from the source?

What experimental term is it when a ruler is dropped to the floor?

Where is most of the energy from incoming waves focused? A. spit B. headland C. underwater D. barrier beach

Exoplanets (planets outside our solar system) are an active area of modern research. Suppose you read an article stating that there is a newly discovered planetary system with three planets.

A car with a mass 1200 kg accelerates at 1.89 m/s2. What is the total force exerted by the car on the road (answer in N to two decimal places) ?