A child on a skateboard is moving at a speed of 2 m/s. After a force acts on the child, her speed is 3 m/s. What can you say about the work done by the external force on the child?
a) positive work was done
b) negative work was done
c) zero work was done
Ans: a) positive work was done
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The NASA lander which deployed the first rover, Sojourner, in 1997 was:
A) Mars Rover. B) Global Surveyor. C) Viking 2. D) South Polar Lander. E) Pathfinder.
A parallel light beam containing two wavelengths, 480. nm and 700. nm, strikes a plain piece of glass at an angle of incidence of 60°. The index of refraction of the glass is 1.4830 at 480. nm and 1.4760 at 700. nm
Determine the angle between the two beams in the glass.
The majority of elements in the Periodic Table are metallic. Does this mean that most minerals are metallic?
What will be an ideal response?
Consider a situation where two moving objects collide and rebound from each other. The energy of a ball rolling up an inclined plane
a. is entirely kinetic b. is entirely potential c. is both kinetic and potential d. none of the above