If an object's mass increases, its------------------------- can be increased

A ball is thrown against a wall and bounces back toward the thrower with the same speed as it had before hitting the wall. Does

lorasvet [3.4K]

Answer:

A) Although the speed is the same, the direction has changed. Therefore, the velocity has changed.

Explanation:

4 0

4 years ago

A race car starting from rest accelerates uniformly at a rate of 4.90 meters per squared. What is the cars speed after it has tr

shusha [124]

Ok, we need to find a relation for the speed as it relates to the acceleration. This is given by the integral of acceleration:

$v= \int\limits^{t}_{0} {a} \, dt' =at$

Where we have the initial velocity is 0m/s and a will be 4.90m/s².

But we see there is an issue now... We know the velocity as a function of time, but we don't know how long the car has been accelerating! We need to calculate this time by now finding the position function as a function of time. This way we can solve for the time, t, that it takes to go 200m accelerating this way and then substitute that time into our velocity equation and get the velocity.
Position is just the integral of velocity:

$s= \int\limits^{}_{} {at} \, dt = \frac{1}{2}at^2$

Where the initial velocity and initial position are both zero.

Now we set this position function equal to 200m and find the time, t, it took to get there

$\frac{1}{2}(a \frac{m}{s^2} )t^2=200m \\ \\ \frac{1}{2}4.90 \frac{m}{s^2} t^2=200m \\ \\ t^2= \frac{400m}{4.90 \frac{m}{s^2}}=81.63s^2 \\ \\ t= \sqrt{81.63s^2 } =9.04s$

Now let's put t=9.04s into our velocity equation:

$v =at=4.9\frac{m}{s^2} \times 9.04s=44.3 \frac{m}{s}$

8 0

3 years ago

Why does the fed rarely change the reserve requirement

Brut [27]

The answer is:

It can be disruptive to the whole banking system.

8 0

3 years ago

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An open pipe is 1.42 m long

lora16 [44]

Answer:

the fundamental frequency produced by the open pipe is 120.78 Hz

Explanation:

Given;

length of the open pipe, L = 1.42 m

speed of sound in air, v = 343 m/s

The length of the open pipe for the fundamental frequency is equivalent to half of wavelength;

$L = \frac{\lambda}{2} \\\\\lambda = 2L$

The fundamental frequency produced by the open pipe is calculated as;

$f_o = \frac{v}{\lambda} \\\\f_o = \frac{v}{2L} \\\\f_o = \frac{343}{2 \times 1.42} \\\\f_o = 120.78 \ Hz$

Therefore, the fundamental frequency produced by the open pipe is 120.78 Hz

6 0

3 years ago

In two or more complete sentences, explain how you can prove that the number of degrees that the Moon rotates around the Earth e

PolarNik [594]

Answer:

Follows are the explanation to this question:

Explanation:

In this solution, it is defined that there are two principal motions for the moon, which are its revolution as well as rotation. In such a movement called revolution, its Moon is relocating around the Earth, in which the approximate movement of the moon from around earth has an average movement of about 13.2° per day, or 92 degrees every week, that's once in 27.3 days.

3 0

3 years ago

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