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Serjik [45]
3 years ago
5

A runner circles the track exactly 2 times for distance of 800m. it takes 4.0min. what is her average speed in m/s? what is her

average velocity?
Physics
1 answer:
Sindrei [870]3 years ago
5 0

If the runner ends where she started, then her total displacement is \Delta x=0\,\mathrm m, which means her average velocity will be

\bar v=\dfrac{\Delta x}{\Delta t}=\dfrac{0\,\mathrm m}{4.0\,\mathrm{min}\cdot\frac{60\,\mathrm s}{1\,\mathrm{min}}=0\,\dfrac{\mathrm m}{\mathrm s}

The total distance she traversed, however, was \Delta d=800\,\mathrm m, which gives her an average speed of

\bar s=\dfrac{\Delta d}{\Delta t}=\dfrac{800\,\mathrm m}{4.0\,\mathrm{min}\cdot\frac{60\,\mathrm s}{1\,\mathrm{min}}=3.3\,\dfrac{\mathrm m}{\mathrm s}

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The launch velocity of the marble launcher is 34.65 m/s

Given that the launch velocity of marble launcher, launches a 25g marble to a distance of 73 cm (0.73 m) and the marble roll up to 6.2 meters before stopping. The launch height is 20 cm (0.2 m).

The time for landing can be calculated by the second equation of motion formula:

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Know more about Launch velocity: -brainly.com/question/18883779

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3 0
1 year ago
How much momentum will a dumb-bell of mass 10 kg transfer
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We want to find how much momentum the dumbbell has at the moment it strikes the floor. Let's use this kinematics equation:

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