Block 1 is attached to a spring and oscillates on a horizontal frictionless tabletop. When block 1 is at a point of maximum displacement, block 2 is brought from above and placed directly on top of block 1 without interrupting the oscillation. The two blocks stick together. How do the period of oscillation and the maximum kinetic energy with both blocks compare to those of block 1 alone? (Hint: assume no work is done on the system when the second block is introduced.)

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Awoman stands a distance d from a loud motor that emits sound uniformly in all directions. the sound intensity at her position is an uncomfortable 2.0×10-3 w/m2. at a distance 2.6 times as far from the motor, what are (a) the sound intensity and (b) the sound intensity level relative to the threshold of hearing?

Which best represents the law of conservation of mass ?