Complete the sentence. Friction always a. helps the motion

b. opposes the motion

c. both of these

d. none of these

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When a 5.0kg cart undergoes a 2.2m/s increase in speed, what is the impulse of the cart

Hydrogen atoms are excited by a laser to the =4n=4 state and then allowed to emit. what is the maximum number of distinct emission spectral lines (lines of different wavelengths) that can be observed from this system? 8 6 2 7 4 5 1 3 calculate the wavelength of the 4⟶14⟶1 transition. =λ=

You can decrease the resistance of a length of wire by