What frequency is received by the ambulance after reflecting from a wall near the person watching the oncoming ambulance (as in the previous problem). the ambulance is moving at 109 km/h and emitting a steady 821-hz sound from its siren

What is a subatomic particle with a negative charge and very little mass?

Which of hubble’s discovery support the big bang theory

Aspring with an unstrained length of 0.071 m and a spring constant of 2.6 n/m hangs vertically downward from the ceiling. a uniform electric field directed vertically upward fills the region containing the spring. a sphere with a mass of 5.29 10-3 kg and a net charge of +7.2 µc is attached to the lower end of the spring. the spring is released slowly, until it reaches equilibrium. the equilibrium length of the spring is 0.058 m. what is the magnitude of the external electric field?