Chứng tỏ rằng các trường véc tơ sau là trường thế và tính Z C
F · dR theo
đường cong trơn từng khúc nào đó nối A(10, −1), B(0, −1, 1).
a. F(x, y, z) = hsin z, −z sin yx cos z + cos yi
b. F(x, y, z) = h3x
2
y
2
z, 2x
3
yz, x3
y
2 − e
−z
i

Since the investigative question has two variables, you need to focus on each one separately. thinking only about the first part of the question, mass, what might be a hypothesis that would illustrate the relationship between mass and kinetic energy? use the format of "if…then…because…” when writing your hypothesis.

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

Which of the following is the phase that results when the moon is on the opposite side of the earth from the sun? a. quarter moon b. crescent moon c. new moon d. full moon