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1 year ago

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A kid on a trampoline has 1,000 J of potential energy when they are at the top of a jump. How much kinetic energy will the kid h

ave when they come halfway down?
a. 100 J
b. 250 J
c. 500 J
d. 1,000 J

1 answer:

emmasim [6.3K]1 year ago

7 0

C: 500 J
Hope this helped!

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Scientist have changed the model of the atom.what experimental evidence led them to change from the previous model .

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Rutherford's model of the atom (ESAAQ) Rutherford carried out some experiments which led to a change in ideas around the atom. His new model described the atom as a tiny, dense, positively charged core called a nucleus surrounded by lighter, negatively charged electrons.

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2 years ago

Radon-220 is a radioactive gas. It escapes from underground rocks and causes a large part of the natural background radiation in

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Answer: 134 neutrons are there in the nucleus of Radon-220

Explanation:

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2 years ago

An automobile with a standard differential turns sharply to the left. The left driving wheel turns on a 20-m radius. Distance be

Inessa05 [86]

Explanation:

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Distance between left and right wheel = 1.5m,

Let us assume speed of drive shaft is N rpm.

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Angular velocity of automobile = w = $\frac{V}{R}$

where, V = linear velocity of automobile m/min,

R = turning radius from automobile center in meter

In the given case, angular velocity remains same for inner and outer wheel but there is change in linear velocity of inner wheel and outer wheel.

Now, we assume that

u = linear velocity of inner wheel

and, u' = linear velocity of outer wheel.

Formula for angular velocity of inner wheel w = ,

Formula for angular velocity of outer wheel w =

Now, for inner wheels

w =

= $\frac{u}{(R - d)}$

u = $V \times \frac{(R - d)}{R}$

= $V \times (1 - \frac{d}{R})$

If radius of wheel is r it will cover distance in one min.

Since, velocity of wheel is u it will cover distance u in unit time(min)

Thus, u = $2\pi rn$ = $V \times (1 - \frac{d}{R})$

Now, rotation per minute of inner wheel is calculated as follows.

n = $\frac{V}{2 \pi r \times (1 - \frac{d}{R})}$

= $\frac{V}{2 \pi r \times (1 - \frac{0.75}{20})}$ (since 2d = 1.5m given, d = 0.75m),

= $\frac{V}{r} \times 0.1532$

So, rotation per minute of outer wheel; n' =

= $\frac{V}{2 \pi r \times (1 + \frac{0.75}{20})}$

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2 years ago

Somebody please help me with this question..!

Rudik [331]

8.1) Here, Pressure increases with depth in the ocean at higher rate then that of increase in altitude in atmosphere. So, the rate of change of pressure is different in these journeys.So, your most correct answer would be option D.

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So, in Short Answers of your questions are:
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2 years ago

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Answer:

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$a_{y}$ = acceleration due to gravity = - 9.8 m/s²

$y$ = position of ball at the time of hitting the smokestack

Using the kinematics equation

$y = y_{o} + v_{oy} t + (0.5) a_{y} t^{2}$

inserting the above values

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2 years ago