No information about friction or air resistance is given Do we include it orr nottt?
I would yes. The most logical way of modelling it, especially in a qualitative question, is as a real object rather than as a perfectly smooth surface with no friction. If you word it carefully you will be able to get the marks regardless of whether they want it or not anyway
But is it possible they give no information about friction or air resistance and just ask the energy conversions? If it is how should i form my answer?
But is it possible they give no information about friction or air resistance and just ask the energy conversions? If it is how should i form my answer?
Well firstly it's more that they haven't mentioned them that kind of gives it away. It is more artificial not to include friction or air resistance, so in most cases if they want you to do so they will tell you in the question. You can easily answer it anyway, e.g. you could say kinetic ----> heat energy (assuming friction is not assumed to be negligible) and then you're fine either way
@samb1234 Lastly if its not a qualitative answer But if they want you to work out something like the kinetic energy at the bottom. No information about friction is given nor asked in any part. So we have no other option then to ignore it in our workings
As either they will ask about friction in some part or give its info. If its neither we just assume it to be 0?
@samb1234 Lastly if its not a qualitative answer But if they want you to work out something like the kinetic energy at the bottom. No information about friction is given nor asked in any part. So we have no other option then to ignore it in our workings
Correct. It's usually fairly easy to tell what you need to do based on what is and isn't given. You aren't given mu or a work done against friction so you obviously can't use them
Just one moree thinggiee. In a qualitative answer. If they state its a SMOOTH plane with the car moving down on a slope and ask the energy conversions.
Smooth means road friction is negligible. Not AIR RESISTANCE.
So how would you answer this? Loss in gravitational energy Gain in kinetic No energy loss in road friction ( smooth plane). What about air resistance?
Just one moree thinggiee. In a qualitative answer. If they state its a SMOOTH plane with the car moving down on a slope and ask the energy conversions.
Smooth means road friction is negligible. Not AIR RESISTANCE.
So how would you answer this? Loss in gravitational energy Gain in kinetic No energy loss in road friction ( smooth plane). What about air resistance?
You can mention it. It isn't wrong so they will not deduct marks for saying it, especially if you were to say that the amount of energy converted into heat through air resistance is probably negligible
right. But what if they are expecting us to write that there is energy loss through air resistance but we write that probably enegy loss through air resistance is negligible. Wont marks be deducted?
right. But what if they are expecting us to write that there is energy loss through air resistance but we write that probably enegy loss through air resistance is negligible. Wont marks be deducted?
You can say that the energy lost to it will be very small compared to the total energy of the system (which is true for a car) which is essentially what negligible means, so you are acknowledging that yes some will be lost to air resistance but contextualising it as being relatively insignificant. Maybe replace neglible with a small amount but it means the same thing
So from your understanding heres what ill write @samb1234
The gravitiational potential energy of the car will ALL be converted to the kinetic energy of the car as there is no loss to road friction as its smooth but there maybe negligible loss as thermal energy due to air resistance.
So from your understanding heres what ill write @samb1234
The gravitiational potential energy of the car will ALL be converted to the kinetic energy of the car as there is no loss to road friction as its smooth but there maybe negligible loss as thermal energy due to air resistance.
Right?
Maybe say the vast majority instead of all, and a small amount instead of negligible. Sorry been working