A toy race car travels around a vertical circle on a curved length of track without ever losing contact?

spongebob

Where is the car when its radial acceleration is smallest?explain..
where is the car when its tangential accelerationis smallest?Explain.
When the car is at the top of the circle, is the acceleration larger than, smaller than, or the same as the acceleration of an object falling freely in a gravitational field?Explain.

Answer
The car has its smallest radial acceleration at the bottom of the circle, because the centripetal acceleration is upwards while the acceleration due to gravity is downwards; since they act in opposite directions, their magnitudes are subtractive, and total magnitude is smaller.

The tangential acceleration is greatest when the car is moving directly dowards, which occurs at the 270 degree position (if the bottom is 0 degrees and it moves through 90 degrees and then to the top at 180 degrees). This is because the centripetal acceleration has no tangential component, so the acceleration due to gravity provides the only tangential component. At 90 and 270 degrees, the downwards force of gravity is actually tangential to the direction of motion, maximizing the tangential acceleration. At 90 degrees, the car is moving upwards, so the force of gravity causes a deceleration. But at 270 degrees, the car is moving downwards and gravity causes it to speed up at its maximum rate.

At the top of the circle, the acceleration is larger than the acceleration of an object falling freely in a gravitational field, because the acceleration is equal to g + (v^2 / r), where g is the free-fall acceleration and v^2 / r is the centripetal acceleration, which will also be downwards. So as long as v is greater than zero, which it must be in order to continue moving around the circle, the acceleration will be larger than that of free-fall.

Toys for Car Seats?

Hilly

I am going to be traveling with my baby to Florida in a few weeks. She is only 8 weeks old but hates to sleep. Any suggestions on some car seat toys that might keep her occupied? Or something that worked for anyone else on long car trips?

Answer
That seems young to travel, But I have no objections to it.

Most places that sell baby toys sell car seat toys that jingle, and have lots of colors, and are fun for the young ones to chew on, another plus is they attach to the car seat so they cant throw the toys or drop them.

But most babies fall asleep on long cars rides. It's soothing to them.
But if it's going to be sunny get sun sheilds for your windows the hot sun with bother her.

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What causes a toy car to turn when you push it across a flat surface?

travel toys in car image

no!ng

I was just playing with a toy car of mine. The wheels don't turn on the car, but whenever I pushed it across the kitchen counter, it also turned to the left or the right. Why doesn't it ever go straight?

Answer
i had a similar problem while building a mousetrap car.

the wheels always remain straight, the the car turns.

i found that the problem was because one of the axles of the car was not level with the chassis of the car itself. this was causing more weight to be on one side of the car.

i know its hard to imagine, but if there is more weight on...lets say the left side of the car... it will raise the coefficient of friction on that side essentially making that wheel(s) on that side spin slower. if the left wheels are spinning slower than the right wheels, the right wheels will travel farther, making the car turn.

Math - If a toy car that can travel 30 miles per hour, was full sized, How fast would it go?

Blank

The toy car is 1/50 of a regular car.

My 9 year old son is very interested in the answer.

He thinks it would travel 1500 miles an hour if it was full sized.
Would it matter if the car was on a hill?

Answer
All other things being equal, your son is correct. If the scaled up wheels are turning the same number of rpms, the car would go 50 times as fast.

However, there are a number of things that don't scale up in a linear way as you increase the dimensions of a solid, mechanical object, including overall mass, friction, etc.

There is also the minor issue of air resistance and controlling a land vehicle at 1500mph (well more than twice the speed of sound).

I am not sure what you mean by being on a hill. Again, if all other things were equal and the model could go up (or down) the hill at 30 mph, then the scale factor would indicate the full-sized version would travel at 1500 mph. Going up a hill would require additional power to overcome the force of gravity if the car was to maintain its speed, and depending on the grade, that could require quite a lot of horsepower--although maintain the speed under any circumstances against the wind resistance at 1500 mph would be quite a challenge.

In simplest terms, the wind resistance, or drag from the air on a moving body increases with the square of the velocity. So even if the larger car could somehow retain the same dynamic properties as the smaller version (which it wouldn't),
increasing the velocity by a factor of 50 would increase the drag by more than 50^2 = 2500 times. So the engine and the tires, although only 50 times larger than in the model, would somehow have to deliver 2500 times as much force, just to overcome the drag.

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Does the weight of a toy car affect the time it takes to travel down a slope?

travel toys in car image

Jorja

I am doing a science experiment and have to do background information (scientific theories/principles that are relevant) on whether the weight of a toy car affects the time it takes to travel down a slope. I don't really know what that means. I have already done the experiment and the heavier the car the faster it will travel. But I don't know how to find the relevant theories or principles for that. Thank you.

Answer
so here is the deal.

When we look at energy for an object falling or on a ramp (it doesn't matter), we can always predict the speed and energy at the bottom. We use this equation to model it:

1/2mv^2(i) + mgh(i) = 1/2mv^2(f) + mgh(f) where i is just initial energy and f is final.

So notice something. Every mass here cancels and if your track were frictionless, weight will have NO effect on the speed of the car on the way down. NO EFFECT! VERY IMPORANT CONCEPT!

However, in the real world, we have something called friction which you saw in your experiment. That is the only reason your car was slower. But, if the car was rolling down the hill, friction should have been a minimum and your cars should have all reach the bottom at the exact same time. Mass has nothing to do with it. If you drop a car down with 100kg vs. 1 kg, they should hit the bottom in the same time. So you timed incorrectly, most likely by human error if you were using a stopwatch.

investigate the energy equations.

What causes a toy car to turn when you push it across a flat surface?

no!ng

I was just playing with a toy car of mine. The wheels don't turn on the car, but whenever I pushed it across the kitchen counter, it also turned to the left or the right. Why doesn't it ever go straight?

Answer
i had a similar problem while building a mousetrap car.

the wheels always remain straight, the the car turns.

i found that the problem was because one of the axles of the car was not level with the chassis of the car itself. this was causing more weight to be on one side of the car.

i know its hard to imagine, but if there is more weight on...lets say the left side of the car... it will raise the coefficient of friction on that side essentially making that wheel(s) on that side spin slower. if the left wheels are spinning slower than the right wheels, the right wheels will travel farther, making the car turn.

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