2. Physics
The tension in the cable of a crane is 2500 N and it lifts a load through 50m, what is the work done on the load?
- 1.25 * 10^5 J
- 2.50 * 10^4 J
- 5.00 * 10^3 J
B
boherbue asked · 22 May 2013
Please explain.
boherbue: cheers
2. Physics - Q&A
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2. Physics
The point at which an applied force overcomes friction and an object begins to move is the co-efficient of
- limiting friction.
- starting friction.
- internal friction.
K
kosala asked · 1 Jan 2012
Lmiting fricion?
alberto: When talking about limiting friction you are talking about a limit of some sort of friction, which when exceeded an object will start to move.Friction can be static, dynamic or rolling. Static friction is that friction which is the the hardest to overcome so when exceeding the limiting friction of static friction you will overcome the static friction and the object will start to move. Rolling friction is the least hard to move so the limiting friction of rolling friction will be less when compaared to static friction.
2. Physics
A mass of 10kg placed 2 metres away from a pivot will have a moment of
- 196 NM.
- 150 NM.
- 980 NM.
E
evamal asked · 18 Mar 2013
How is this calculated ?
trap2307: Hello! 10*9.81*2=196.2 NM 9.81 - acceleration of gravity
2. Physics
A pilot requests 9.2 tonnes of fuel. The bowser driver reports to the pilot that the specific gravity is 0.8, what will the uplift be?
- 10200 litres.
- 11500 litres.
- 14375 litres.
F
faris92 asked · 31 Jan 2013
Can someone explain this ?
trap2307: If specific gravity of fuel is 0.8 and weight of fuel is 9200kg, volume of this quantity of fuel will be bigger than 7360litres or 9200litres. So it is 11500... Or just divide it without calculator, if it easiest way for you.
2. Physics
Transfer of heat from a hot area to a cold area by direct molecular contact is
- conduction.
- convection.
- refraction.
N
Nino asked · 5 Dec 2012
Area should be defined for this question. if solid yes your answer is right otherwise all 3 choices are correct.
PART66Online: Convection is a transfer of 'matter' from one place to another. Radiation is a system which heats up anything in its path. but heat is not 'transferred'.
2. Physics
Two Vectors are at 90 degrees to each other having magnitudes of 3N and 4N. The resultant is
- 5N.
- 1N.
- 7N.
T
talhamalik88 asked · 5 Nov 2012
how??
talhamalik88: ok ..thanks
2. Physics
The work done in lifting a mass of 2000 kg vertically to a height of 40 metres is
- 392.4 kJ.
- 784.8 kJ.
- 196.2 kJ.
J
jawwadbaig asked · 20 Oct 2012
how?
faris92: First is o find force acting towards gravity; F=mg 2000x9.8 =19600 then find work with height 40m W=force x distance W=19600x40 =784000J or 784kJ
2. Physics
The fundamental frequency of a control cable is 10 Hz, the frequency of the 2nd Harmonic is
- 10 Hz.
- 20 Hz.
- 40 Hz.
P
pannam asked · 11 Oct 2012
any help with this ?
MridulDev: physicsclassroom.com/class/sound/u11l...
2. Physics
The angular velocity of 500 RPM is, in rads/seconds is equal to
- 33.33pi rads/s.
- 52.36pi rads/s.
- 16.66pi rads/s.
P
pannam asked · 11 Oct 2012
how ?
MridulDev: omega = 2*Pi*R, so (500/60)*2*Pi {change revolution per min to revolution per sec} = 8.33 * 2 * Pi = 16.66*Pi.
2. Physics
In which medium does sound travel the fastest?
- Steel.
- Glass.
- Water.
F
farhan_muddz asked · 18 Sep 2012
is it steel?
PART66Online: Yes, it is steel. Check this article: en.wikipedia.org/wiki/Speed_of_sound
2. Physics
The Mass of a Proton is approximately
- approximately 500 times the mass of an electron.
- equal to approximately half the mass of a neutron.
- 2000 times greater than the mass of an electron.
Y
yousif.zayani asked · 2 Jul 2012
mass of proton is = mass of an electron thats the answer ?
PART66Online: Hey! Answer is right. Check this for example: school-for-champions.com/science/atom...
2. Physics
An ice melted into a liquid will take up
- less space.
- same space.
- more space.
R
rizkaramat asked · 15 Apr 2012
PL SOMEBODY HELP OUT
61478939: Because the density of ice is less than water but the mass is the same.In winter,you can see some ice is floating on water.I hope this can help you
2. Physics
If heat is constant, and if pressure increases on a liquid what will the volume do?
- Slowly increases.
- Remains constant.
- Slowly decreases.
R
rizkaramat asked · 15 Apr 2012
how?
PART66Online: Liquids are considered incompressible, therefore their volume remains constant.