If a spring constant is 40 n/m and an object hanging from it stretches it 0.50 m, what is the mass of the object?

What is tan(61)? а. 1.80 b. 0.49 c. 0.61 d. 0.87

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Which is not true about oxygen-17 and oxygen-18?