PHL245H5 Study Guide - Midterm Guide: Madea

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greyturtle111

5 Dec 2012

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Part i symbolize each of the following sentences on the basis ortnjscheme of abbreviation that accompanies it. (3 points each: 30 points totalj. If taxes are raised, then the economy will improve if the stock market is steady. [p: taxes are raised; e: the economy-will improve; r: the stock market is s teadyj. 2" if taxes are raised and the stock market is steady, then the economywill improve unless the government does not increase spending. [p: taxes are raised; q: the stock market is steady; r: the economy will improve; s: the government increases. R: the government grants subsidies to domestic produce; s: the government finds new sources of revenuej. Irn u c u : the dollar will fall if stock market prices do not increase; otherwise it won"t. (p: the dollar will fall; q: stock. ^,/l n&u -4 nt tr" i prlces t{>"|u ftdal.

Related Questions

Good Vibes: Introduction to Oscillations

The conditions that lead to simple harmonic motion are as follows:

There must be a position of stable equilibrium.

There must be a restoring force acting on the oscillating object. The direction of this force must always point toward the equilibrium, and its magnitude must be directly proportional to the magnitude of the object's displacement from its equilibrium position. Mathematically, the restoring force F⃗ is given by ⃗, where is the displacement from equilibrium and k is a constant that depends on the properties of the oscillating system.

The resistive forces in the system must be reasonably small.

Consider a block of mass m attached to a spring with force constant k, as shown in the figure(Figure 1) . The spring can be either stretched or compressed. The block slides on a frictionless horizontal surface, as shown. When the spring is relaxed, the block is located at x=0. If the block is pulled to the right a distance A and then released, A will be the amplitude of the resulting oscillations.

Assume that the mechanical energy of the block-spring system remains unchanged in the subsequent motion of the block.

Part A

After the block is released from x=A, it will

(a) remain at rest

(b) move to the left until it reaches equilibrium and stop there.

(d) move to the left until it reaches x=−A and then begin to move to the right.

The time it takes the block to complete one cycle is called the period. Usually, the period is denoted T and is measured in seconds.

The frequency, denoted f, is the number of cycles that are completed per unit of time: f=1/T. In SI units, f is measured in inverse seconds, or hertz (Hz).

Part B

If the period is doubled, the frequency is

(a) unchanged

(b) doubled

Part C

An oscillating object takes 0.10 s to complete one cycle; that is, its period is 0.10 s. What is its frequency f?

Express your answer in hertz.

Part D

If the frequency is 40 Hz, what is the period T?

Express your answer in seconds.

The following questions refer to the figure (Figure 2) that graphically depicts the oscillations of the block on the spring.

Note that the vertical axis represents the x-coordinate of the oscillating object, and the horizontal axis represents time.