Physics

A sculptor and his assistant are carrying a wedge-shaped marble slab up a flight of stairs, as shown in the figure

Question: A sculptor and his assistant are carrying a wedge-shaped marble slab up a flight of stairs, as shown in the figure. The density of the marble is uniform. Both are lifting straight up as they hold the slab completely stationary for a moment. Does the sculptor have to exert more force than the assistant …

A sculptor and his assistant are carrying a wedge-shaped marble slab up a flight of stairs, as shown in the figure Read More »

An object is placed 20.0 cm from a converging lens with focal length 15.0 cm (see the figure, not drawn to scale)

Question: An object is placed 20.0 cm from a converging lens with focal length 15.0 cm (see the figure, not drawn to scale). A concave mirror with focal length 10.0 cm is located 75.0 cm to the right of the lens, (a) Describe the final image—is it real or virtual? Upright or inverted? (b) What …

An object is placed 20.0 cm from a converging lens with focal length 15.0 cm (see the figure, not drawn to scale) Read More »

Bryce Canyon National Park, shown in the accompanying photo, is in dry southern Utah

Question: Bryce Canyon National Park, shown in the accompanying photo, is in dry southern Utah. It is carved into the eastern edge of the Paunsaugunt Plateau. Erosion has sculpted the colorful limestone into bizarre shapes, including spires called “hoodoos.” As you and a companion (who has not studied geology) are viewing the scenery in Bryce …

Bryce Canyon National Park, shown in the accompanying photo, is in dry southern Utah Read More »

An automobile engine slows down from 4500rpm…

Question: “an automobile engine slows down from 4500rpm to 1200rpm in2.5seconds..Calculate..A) Angular Acceleration assumed constant, andB) The total number of revolutions the engine makes in this time” Answer: α=(ω2-ωo2)/t, so first convert the rpm’s torad/s then you get 472.5rad/s and 126rad/s andthe acceleration is -138.6rad/s2. The total revolutions that are made areΔθ=1/2Δωt=748rads, so748rads/2Ï€=1.2x102revolutions