chiếu 1 tia sáng lên 1 gương phẳng, thu được tia phản xạ tạo với tia tới 1 góc 70. tính giá trị của góc tới và góc phản xạ

The earth is constantly spinning on its axis, like you might spin a basketball on your finger. it is this spinning of the earth that causes

Astudent throws a water balloon with speed v0 from a height h = 1.76 m at an angle θ = 21° above the horizontal toward a target on the ground. the target is located a horizontal distance d = 9.5 m from the student’s feet. assume that the balloon moves without air resistance. use a cartesian coordinate system with the origin at the balloon's initial position. (a) what is the position vector, rtarge t, that originates from the balloon's original position and terminates at the target? put this in terms of h and d, and represent it as a vector using i and j. (b) in terms of the variables in the problem, determine the time, t, after the launch it takes the balloon to reach the target. your answer should not include h. (c) create an expression for the balloon's vertical position as a function of time, y(t), in terms of t, vo, g, and θ. (d) determine the magnitude of the balloon's initial velocity, v0, in meters per second, by eliminating t from the previous two expressions.

We will use a video to study faraday’s law of electromagnetic induction by analyzing the induction that occurs due a coil of copper wire sliding along an air track that passes through an external magnetic field. specifically, we will: examine some of the main principles behind faraday’s law. apply lenz’s law to determine the direction of the induced emf. take measurements of the induced emf from the voltmeter as the coil passes into and out of the external magnetic field. use the horizontal scale provided to determine the speed of the coil. calculate the magnetic field induced in the coil as it passes into and out of the external magnetic field.