Two resistors, R1 and R2, are connected in parallel. R2 = 221.0
ohms, and the equivalent resistance
of the combination is 120.7 ohms.
What is the value of R1?
(Unit = ohm)

Awoman holds a book by placing it between her hands such that she presses at right angles to the front and back covers. the book has a mass of m = 1.8 kg and the coefficient of static friction between her hand and the book is μs = 0.67. no attempt 50% part (a) what is the weight of the book, fgb in newtons?

How do we measure or think of speed in the united states?

Photons with the highest energy have the longest period