The bohr model of the hydrogen atom pictures the electron as a tiny particle moving in a circular orbit about a stationary proton. in the lowest-energy orbit the distance from the proton to the electron is 5.29 x 10-11 m, and the linear speed of the electron is 2.18 x 106 m/s. a) what is the angular velocity of the electron? b) how many orbits about the proton does the electron make each second? c) what is the electron❝s centripetal acceleration?

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

Chameleons catch insects with their tongues, which they can rapidly extend to great lengths. in a typical strike, the chameleon's tongue accelerates at a remarkable 220 m/s2 for 20 ms, then travels at constant speed for another 30 ms.

Which statement is true? a) the work done to lift an object 6 meters is greater than the gravitational potential energy it gains. b) the work required to push an object is less than the work required to pull an object the same distance. c) the work required to raise an object to a height is equal to the gravitational potential energy the object gains. d) the work done against gravity to lift an object straight up is greater than the work required to roll it up a ramp.