Which proton is used as a beam to treat cancer

What is the name of the perceived change in a sound wave’s frequency due to motion between the observer and the sound source?

Acar jack with a mechanical advantage of 6 needs to produce an output force of 600 n to raise a car. what input force is required? 6 n 100 n 600 n 3,600 n

Estimate the kinetic energy of mars with respect to the sun as the sum of two terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. (assume mars is a uniform sphere with mass = 6.4×10 to the power of 23 kg, radius = 3.4×10 to the power of 6 m, rotation period = 24.7 hours, orbital period = 686 days and is 2.3×10 to the power of 8 km from the sun.)