Un bloque de 3Kg de masa es empujado contra una pared mediante una fuerza P que forma un
ángulo de Ѳ=50° con la horizontal, como se muestra en la figura. El coeficiente de fricción estático
entre el bloque y la pared es de 0,25. Determine el valor de la fuerza P que permite al bloque
permanecer fijo

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies.

Follow these directions and answer the questions. 1. set up the ripple tank as in previous investigations. 2. bend the rubber tube to form a "concave mirror" and place in the ripple tank. the water level must be below the top of the hose. 3. generate a few straight pulses with the dowel and observe the reflected waves. do the waves focus (come together) upon reflection? can you locate the place where the waves meet? 4. touch the water surface where the waves converged. what happens to the reflected wave? 5. move your finger twice that distance from the hose (2f = c of c, center of the curvature) and touch the water again. does the image (the reflected wave) appear in the same location (c of c)? you may have to experiment before you find the exact location. sometimes it is hard to visualize with the ripple tank because the waves move so quickly. likewise, it is impossible to "see" light waves because they have such small wavelengths and move at the speed of light. however, both are examples of transverse waves and behave in the same way when a parallel wave fronts hit a curved surface.

A-of 75 cm by cm by 17.5 cm up. of is 2 kg a , in ,if it is in , kg/?