Final answer:
The provided questions explore basic physics concepts, such as vector addition, average speed versus velocity, acceleration interpretation on graphs, the normal reaction force, and the efficiency of simple machines. The key understanding is that vectors require both direction and magnitude for proper addition, and that not all physical quantities correlate as one might initially presume.
Step-by-step explanation:
Physics Equation Concepts
True or False-If only the angles of two vectors are known, we can find the angle of their resultant addition vector. The answer is b. False. Without the magnitudes of the vectors, we cannot determine the resultant vector's direction accurately.
True or False: The average speed of the ball will be less than the average velocity of the ball. The answer is a. True if the ball changes direction during its motion, as average velocity is direction dependent, whereas average speed is not.
True or False: The position vs time graph of an object that is speeding up is a straight line. The answer is b. False. A graph representing an object that is speeding up will typically show a curve, indicating acceleration.
True or False-Normal reaction is the force that opposes the force of gravity and acts in the direction of the force of gravity. This statement is b. False. Normal reaction is actually the force that opposes the force of gravity but acts perpendicular to the surface of contact.
True or false-The efficiency of a simple machine is always less than 100 percent because some small fraction of the input work is always converted to heat energy due to friction. The answer is a. True, as due to friction and other inefficiencies, no machine is perfectly efficient.