Bicycle VS Moped - Bang Goes The Theory

[goatwarden]

Ford's Parts Warehouse in Daventry with the doors shut. The floor there follows the curvature of the Earth !

Is that building used to store urban myths? When I worked at Cummins, across the road, many years ago the Ford warehouse seemed to be the basis of a number of unresearched "facts" relating to its size.

[snibgo]

Once a vehicle is up to speed, its momentum ( inertia ) keeps it rolling, therefore 'steady state' consumptions are less than a light vehicle. FOR THE SAME FRONTAL AREA. Remember how the heavy cars on your Hot Wheels track kept rolling further
Putting rocks in the bike's panniers would increase its inertia for the same X section frontal area, and be easier to maintain a steady speed.
Only the accellerating phase of the test would be more energy demanding. [FALSE]
A car with a load of luggage will roll for longer along a flat than an empty car.

You may be confusing two observations.

The first is that an unpowered vehicle will decelerate (due to rolling and air resistances) less when the vehicle weighs more.

The second is that to maintain a constant speed, a heavier vehicle needs more power than a lighter vehicle. (This is because the rolling resistance is proportional to the mass.) At high speeds, air resistance dominates over rolling resistance, so we may not notice this effect.

[fatboy]

So if this program inspires your daughter into science or engineering it has worked.

More likely to do this than me grumbling about working in engineering! Mind you all my kids have liked seeing my work's antenna anechoic chamber test facility (basically a very expensive room with pyramidal structures made from material that absorbs radio signals and some power motors to spin things around!). So much so that their trip out on Good Friday was to visit it (i.e. I went to work!).

[squeaker]

Good old family viewing and educational. So far this series seems to be themed about human powered things compared to internal combustion power.
From a teaching point of view it has worked in that you demonstrate something the get the students to evaluate the outcome and even try their own experiments.
The method is not the important part but the outcome, the students wanting to know more.

So if this program inspires your daughter into science or engineering it has worked.

Well said Keith.

+1. It's not supposed to be a rigorous scientific experiment (try watching the OU for that), just a 'what goes further on 1000 calories?' illustration that prods the viewers' little grey cells.

[pete75]

Ford's Parts Warehouse in Daventry with the doors shut. The floor there follows the curvature of the Earth !

Is that building used to store urban myths?

Good one!

[pete75]

This is almost a moped - well 50 cc anyway - wonder how a bike would compare with that little gem...
http://www.bikeexif.com/suzuki-rk67

[niggle]

This is almost a moped - well 50 cc anyway - wonder how a bike would compare with that little gem...
http://www.bikeexif.com/suzuki-rk67

Yes indeed, Suzuki really did benefit from Walter Kaaden's 2-stroke tuning genius after Ernst Degner defected to Suzuki from East Germany and MZ... But to even things up you should really compare it with something like this:

[pete75]

This is almost a moped - well 50 cc anyway - wonder how a bike would compare with that little gem...
http://www.bikeexif.com/suzuki-rk67

Yes indeed, Suzuki really did benefit from Walter Kaaden's 2-stroke tuning genius after Ernst Degner defected to Suzuki from East Germany and MZ... But to even things up you should really compare it with something like this:

Well with that sort of streamlining a fair comparison would be with this...

[niggle]

This is almost a moped - well 50 cc anyway - wonder how a bike would compare with that little gem...
http://www.bikeexif.com/suzuki-rk67

Yes indeed, Suzuki really did benefit from Walter Kaaden's 2-stroke tuning genius after Ernst Degner defected to Suzuki from East Germany and MZ... But to even things up you should really compare it with something like this:

Well with that sort of streamlining a fair comparison would be with this...

Or this:

[PhilWhitehurst]

Well for me it said that not only was cycling 4 times more efficient than the moped when moving the same weight. But also it allows you to transport 60kg of additional goods when on the bike whilst achieving that efficiency gain.

[Alex L]

Clearly the observation here is that yellow bikes move fastest.

[Edwards]

Clearly the observation here is that yellow bikes move fastest.

My observation is I want the yellow trike.

They have done flying and now carrying a load on land. Is something underwater next?

If so what sub should they compete with?

[Alex L]

French Engineers Design a Pedal-Powered Submarine

[squeaker]

French Engineers Design a Pedal-Powered Submarine

Nothing new

[Ayesha]

I'm a master of the sweeping statement, but you beat me hands down!

All floors follow the curvature of the Earth because they are level.

A car lightly loaded can run further than a car fully loaded - this may happen because the tyres need extra air because of the weight.

There is a difference between a surface being 'level' and being 'flat'. Your house's floor is 'flat'.

Most floors DON'T follow the curvature of the Earth. They are either drawn using one spirit level and a length of string pulled tight, or a laser level,,, both of these are misnomers...

Only floors which are two-part epoxy liquid will settle to ABSOLUTE level.

The floorboards in your house were 'levelled' by the chippy putting a spirit level on the joists. If he/she used the spirit level in the centre of the house, the ends of the floorboards at the walls will both be on the up-hill slightly.

The floor at Ford's Dagenham parts warehouse were levelled using a Water Level, which is a flexible hose with a sight glass at each end. The water level in the sight glasses will always be the same distance from the Earth's centre, unless the moon is particularly powerful that day,,,

The Motor Industry Research Association has a pair of level parallel straights which follow the Earth's curvature. If they were FLAT, the ends would be going uphill. One particular road in southern Spain follows the Earth's curvature. If it was FLAT, the ends would be at nearly 5% gradient. Shakespeare County Raceway where the BBC filmed was RAF Long Marston in Warwicksire. The runway was constructed to follow the Earth's curvature using a long length of hose and two sight glasses. So was Santa Pod ( RAF Podington ) and so was the main straight at Silverstone ( RAF Silverstone ).

If a shop fitter puts a shelf up in a store using a laser level, only ONE point on it will be 'level'. It will be 'flat' and the ends will be on the up gradient, forcing a billiard ball to roll to that one point.


Sorry Mick. A heavier car will roll further because it has a greater kg force for the same exterior dimensions. A heavier vehicle will achieve a greater 'equilibrium velocity' down a hill for the same exterior dimensions. This is "Fat lad's advantage".

Try rolling a table tennis ball and a steel ball of the same size down a Hot Wheels track. ( Make sure the door is closed because a gust of wind will blow the table tennis ball back up the slope )