(5) The dual nature of the electron means that it has \( \begin{array}{ll}\text { a. a mass and a charge. } & \text { b. a charge and a wave motio } \\ \text { c. a volume and a wave motion. } & \text { d. a mass and a density. }\end{array} \)

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

Um veículo parte do repouso em movimento retilineo e acelera com aceleração escalar constante e igual a \( 2 \mathrm{~m} / \mathrm{s}^{2} \). Pode-se dizer que sua velocidade escalar e a distância percorrida após 3 segundos, valem, respectivamente: a) \( 2 \mathrm{~m} / \mathrm{s} \) e 12 m b) \( 12 \mathrm{~m} / \mathrm{s} \) e 35 m c) \( 3 \mathrm{~m} / \mathrm{s} \) e 12 m d) \( 6 \mathrm{~m} / \mathrm{s} \) e 18 m e) \( 6 \mathrm{~m} / \mathrm{s} \) e 9 m

A satellite with a mass of 150 kg fires its engines to increase velocity, thereby increasing the size of its orbit about Earth. As a result, it moves from a circular orbit of radius \( 7.5 \times 10^{6} \mathrm{~m} \) to an orbit of radius \( 7.7 \times 10^{6} \mathrm{~m} \). What is the approximate change in gravitational.force from Earth as a result of this change in the satellite's orbit? (Recall that Earth has a mass of \( 5.97 \times 10^{24} \mathrm{~kg} \) and \( G=6.67 \times 10^{-11} \mathrm{~N} \cdot \mathrm{~m}^{2} / \mathrm{kg}^{2} \).) A. -54 N B. -216 N C. -113 N D. -148 N

Which of the following best describes the magnetic field lines around an isolated, permanent bar magnet? A. The field lines go from the magnet's north pole into its south pole. B. The field points straight into the bar magnet along radial lines that extend to infinity. C. The field points out along radial lines from the bar magnet, extending straight out to infinity. D. The field lines go from the magnet's south pole into its north pole.

3) Un ragazzo, partendo da fermo, scende lungo uno scivolo ad acqua. Arriva alla fine dello scivolo con una velocità di \( 12 \mathrm{~m} / \mathrm{s} \). Quanto era alto lo scivolo?