A QUE DISTANCIA SOBRE UNA MESA DEBE COLOCARSE UNA FUENTE DE 50 cd, PARA QUE PRODUZCA SOBRE ELLA LA MISMA INTENSIDAD QUE PRODUCIRIA UNA LAMPARA DE 150 cd UBICADA A 10 m DE DISTANCIA.

28. a stone is projected at a cliff of height h with an initial speed of 42.0 mls directed at angle θ0 = 60.0° above the horizontal. the stone strikes at a, 5.50 s after launching. find (a) the height h of the cliff, (b) the speed of the stone just before impact at a, and (c) the maximum height h reached above the grou

Which of the following changes will result in a stronger electromagnet? a. using fewer coils of wire b. using a higher voltage c. using a shorter nail d. using a longer wire

Which of the following forces require physical contact? tension air resistance friction magnetic force applied force