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4 years ago

How long will it take them to glide to the edge of the rink?

1 answer:

8 0

At the center of a 50 m diameter circular ice rink, if a 77 kg skater traveling at 2.3 m/s and then collides with a 63 kg skates traveling at 3.7 m/s. This is how long it will take them to glide to the edge of the rink:

Speed after the collision= √{[77(2.3)77^2] + [63(3.7)^2]} / (77+63)=2.09 m/s

For them to be able to get to the edge which is 50 m away it will take them 23.9 seconds.

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How do you complete this circuit?

ale4655 [162]

Explanation:

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7 0

3 years ago

An object moving due to gravity can be described by the motion equation y=y0+v0t−12gt2, where t is time, y is the height at tha

LenaWriter [7]

Answer:

$t=6.4534 s$

Explanation:

This is an exercise where you need to use the concepts of free fall objects

Our knowable variables are initial high, initial velocity and the acceleration due to gravity:

$y_{0}=75m$

$v_{oy} =20m/s$

$g=9.8 m/s^{2}$

At the end of the motion, the rock hits the ground making the final high y=0m

$y=y_{o}+v_{oy}*t-\frac{1}{2}gt^{2}$

If we evaluate the equation:

$0=75m+(20m/s)t-\frac{1}{2}(9.8m/s^{2})t^{2}$

This is a classic form of Quadratic Formula, we can solve it using:

$t=\frac{-b ± \sqrt{b^{2}-4ac } }{2a}$

$a=-4.9\\b=20\\c=75$

$t=\frac{-(20) + \sqrt{(20)^{2}-4(-4.9)(75) } }{2(-4.9)}=-2.37s$

$t=\frac{-(20) - \sqrt{(20)^{2}-4(-4.9)(75) } }{2(-4.9)}=6.4534s$

Since the time can not be negative, the reasonable answer is

$t=6.4534s$

8 0

3 years ago

A friend claims that throwing a baseball up towards the school roof illustrates gravitational potential energy transforming into

Cloud [144]

Answer:

The Statement is wrong because the reverse is the case as it is the kinetic energy that is being transformed to gravitational potential energy.

Explanation:

As your friend throws the baseball into the air the ball gains an initial velocity (u) and this makes the Kinetic energy to be equal to

$KE = \frac{1}{2} mu^2$

Here m is the mass of the baseball

Now as this ball moves further upward the that velocity it gained reduce due to the gravitational force and this in turn reduces the kinetic energy of the ball and this kinetic energy lost is being converted to gravitational potential energy which is mathematically represented as (m×g×h)

as energy can not be destroyed but converted to a different form according to the first law of thermodynamics

Looking a the formula for gravitational potential energy we see that the higher the ball goes the grater the gravitational potential energy.

4 0

4 years ago

Which way do electric field lines point?

Jlenok [28]

At any point, the electric field points in the direction of the force
on a positive point-charge located there. So the lines point away
from a positive charge, and toward a negative one.

4 0

3 years ago

How long does it take an airplane to fly 5000m if it maintains a speed of 240 meters per second

Rudiy27

Answer:

20.83

Explanation:

5000/240

7 0

3 years ago

Read 2 more answers