\( f^{\prime}=\left(\frac{v+v_{0}}{v}\right) f \) You are riding in a car at a velocity \( v_{0} \), in meters per second, towards a loud block party. Because of this movement, the actual frequency of the sound waves emitted by the speakers, \( f \), in hertz, is perceived by you to be a different frequency \( f^{\prime} \), in hertz. The speaker's sound waves travel at a velocity \( v \), in meters per second. This phenomenon is called the Doppler effect. The formula above shows the relationship between these variables. If the velocity of the car is 22 m/s, the velocity of the sound waves of the speaker is 340 m/s and you perceive the frequency of the speaker's sound waves to be 500 Hz. Which of the following is the closest to the actual frequency of the speaker's sound waves? A. 469 B. 532 C. 470 D. 533

Um motorista conduzia seu carro a \( 90 \mathrm{~km} / \mathrm{h} \), quando avistou um sinal fechado a frente e acionou o freio, que proporcionou uma desaceleração constante de \( 5 \mathrm{~m} / \mathrm{s}^{2} \) até a

Un'auto da corsa ha una massa di 800 kg . Parte da ferma e percorre 35 m in \( 3,0 \mathrm{~s} \), accelerando costantemente per tutto il tempo. Trascura l'attrito. - Quanto vale la forza esercitata dai motori dell'auto nell'intervallo di tempo dato? \( \left[6,2 \times 10^{3} \mathrm{~N}\right] \)

A body weighs 3.1 N in air and 2.2 N when completely immersed in water of density \( 1000 \mathrm{~kg} / \mathrm{m}^{3} \). Calculate the volume of the body. Take the gravitational acceleration as \( 9.81 \mathrm{~m} / \mathrm{s}^{2} \).

Ejercicio 5: Relación entre trabajo y energía cinética Un automovil de 1000 kg acelera desde \( 0 \mathrm{~m} / \mathrm{s} \) hasta \( 20 \mathrm{~m} / \mathrm{s} \). ¿Cuánto trabajo realiza el motor para alcanzar esa velocidad? Fórmula: \[ \mathrm{HI}=\Delta K E=\frac{1}{2} m\left(v_{f}^{2}-v_{i}^{2}\right) \]

1. Seed climbs a rock that is 50 meters high. If Seed has a mass of 60 kg , answer the following: a. Which theorem and formula can be used to calculate the work done by gravity in this scenario? b. Using this theorem, calculate the work done by gravity as Seed climbs the rock. Show your calculations.