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3 years ago

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A bowling ball rolls 33\,\text m33m33, start text, m, end text with an average speed of 2.5\,\dfrac{\text m}{\text s}2.5 s m 2

, point, 5, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction. How many seconds did the ball roll?

1 answer:

asambeis [7]3 years ago

4 0

The ball rolled for 13.2 s

<h3>Further explanation</h3>

Speed is scalar and no direction

$\tt avg~speed=\dfrac{total~distance}{elapsed~time}=\dfrac{\Delta x}{\Delta t}$

A bowling ball rolls 33 m, with average speed = 2.5 m/s

So elapsed time :

$\tt t=\dfrac{33~m}{2.5`m/s}=13.2~s$

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Explanation:

A race car's main target is how to have rapid acceleration by scaling its speed. Acceleration of car is mostly a product of the force of the car engine.

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It is also written mathematically as:

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a is the acceleration.

Re-writing the equation:

Now Acceleration = $\frac{Force }{mass}$

We can see that acceleration is directly related to increasing force but inversely proportional to the mass.

A race car needs to have a good acceleration so as to attain top speed.

The more the mass, the less the acceleration.

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3 years ago

A car starts from rest at the top of a hill with 45 J of gravitational

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Answer:

<em>The car will be moving at 5.48 m/s at the bottom of the hill</em>

Explanation:

<u>Principle of Conservation of Mechanical Energy</u>

In the absence of friction, the total mechanical energy is conserved. That means that

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When the car is at the top of the hill, its speed is 0, but its height h should be enough to produce the needed speed v down the hill.

The Kinetic energy is then, zero. When the car gets enough speed we assume it is achieved at ground level, so the potential energy runs out to zero but the Kinetic is at max. So the initial potential energy is transformed into kinetic energy.

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3 years ago

Lindsay is planning a flight from St. Catherines to Hamilton, which lies due west of St. Catharines.

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Lindsay should fly the plane in the direction [W 12.5° S] to get Hamilton.

Using Sine rule to solve this question

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2 years ago

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4 years ago

Read 2 more answers

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aniked [119]

Answer:

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The work done on the ball is equal to the kinetic energy gained by the ball:

$W=K$

So when the work done doubles, the kinetic energy doubles as well:

$2W = 2 K$

However, the kinetic energy is given by

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where

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4 years ago