universalcj
Badges: 12
Rep:
?
#1
Report Thread starter 1 year ago
#1
for a level edexcel physics
what' the exact definition of dark matter ?
cuz from the book , it says that dark matter does not Emit light

but according to the past paper 2012 jan unit 5 q5 it says the key feature of dark matter is that it emits no detectable electromagnetic - radiation

I'm a bit confused....
0
reply
nzy
Badges: 17
Rep:
?
#2
Report 1 year ago
#2
The two are basically saying the same thing. "Light" could refer to both visible light, which is just EM radiation in a particular range of the electromagnetic spectrum, or (more broadly, and this case) all electromagnetic radiation. If in doubt, go with the past paper answer - it's more specific and clears up any ambiguity that might lose you marks in an exam.
2
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Feeling behind at school/college? What is the best thing your teachers could to help you catch up?

Extra compulsory independent learning activities (eg, homework tasks) (5)
3.85%
Run extra compulsory lessons or workshops (22)
16.92%
Focus on making the normal lesson time with them as high quality as possible (23)
17.69%
Focus on making the normal learning resources as high quality/accessible as possible (17)
13.08%
Provide extra optional activities, lessons and/or workshops (39)
30%
Assess students, decide who needs extra support and focus on these students (24)
18.46%

Watched Threads

View All