Does observing a physical property of a substance change the identity of the

substance? Explain your answer.

Which part of the eye controls whether or not the pupil dilates or constricts? iris retina optic nerve cornea

How does current change for resistors in series? what is the equivalent resistance for resistors in series? answers?

What are the element names for the following symbols? Ni, He, Pb

The electric field of a charge is defined by the force on what kind of particle?

How to convert 60km/h into m/s?

Two railroad cars, each of mass 6500 kg and traveling 80 km/h in opposite directions, collide head-on and come to rest. how much thermal energy is produced in this collision?

What is a result of using a machine?

A boy rides motorbike with velocity of 20 m/s He accelerates his motorbike to a velocity of 30 m/s for 5 second. Calculate the acceleration produced in the motorbike. [Ams 2ms

How is a star's emission spectrum used to study stars?

A 52.0 kg skateboarder does a trick on a half-pipe. During the trick, he reaches a speed of 8.90 m/s. The radius of the half-pipe ramp is 3.00 meters. What is the minimum centripetal force necessary to keep the skater on the ramp?