Which of the two fundamental forces are attractive only? weak and strong

weak and electromagnetic

strong and electromagnetic

strong and gravitational

Sarah and michelle work at a tech company that designs exercise apps. sarah tells michelle she has heard that james, their supervisor, interviewed with a competitor and may be leaving the company, which would open up a management position. what kind of power is sarah exerting?

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.

Scientific models are based on current knowledge, which can limit their effectiveness when new discoveries are made.