A block of mass M on an inclined surface is attached to a spring of negligible mass, as shown. The other end of the spring is attached to a wall, and there is negligible friction between the block and the incline. The block is pulled to a position such that the spring is stretched from its equilibrium position. The block
hen released from rest. Which of the following systems can be classified as a closed system?
А
A system consisting of the block only
B
A system consisting of the spring and Earth
С
A system consisting of the block and spring
D
A system consisting of the block, spring, and Earth

If you touch a hot light bulb and get burned, that is an example of a. radiation b. convection c. conduction

Alinearly polarized electromagnetic wave has an average intensity of 196 w/m^2. this wave is directed towards two ideal polarizers (in real polarizers, transmission is also effected by reflection and absorption). polarizer a is oriented with its transmission axis at an angle of θ_1=20.8∘ with the incident electric field. polarizer b has its axis at an angle of θ_2=63.0∘ with the incident electric field. what is the average intensity of the wave after it passes through polarizer a? what is the average intensity of the wave after it passes through polarizer b? suppose that the two polarizers a and b are interchanged. what would the average intensity be after passing through both polarizers?

Abike rider starts from rest and accelerates 28.0 meters down a slope in 5.00 seconds. what is her acceleration? select one: a. 3.21 m/sec2 b. 1.75 m/sec2 c. 9.80 m/sec2 d. 2.24 m/sec2