# Posts by 4611star

Total # Posts: 18

**maths**

the length of a rectangle is twice its width, the area is 72sq inches,find its dimensions(find length and width)

**maths**

find two even integers(numbers) so that the square of the smaller is 10 more than the larger one

**maths**

what is the quadratic equation?

**physics! HELP!**

A filament lamp- cost- 80p effiency- 0.2 expected life- 1000 hours a compact fluorescent lamp (CFL)- cost- £3.00 effiency- 0.8 expected life- 8000 hours a filament lamp with a power rating of 100W gives 2000 units of light. what power rating would a CFL need to provide ...

**chemistry**

which of the following are non- polluting: renewable sources coal nuclear fuels or oil?

**physics**

1A) A filament lamp- cost- 80p effiency- 0.2 expected life- 1000 hours a compact fluorescent lamp (CFL)- cost- £3.00 effiency- 0.8 expected life- 8000 hours a filament lamp with a power rating of 100W gives 2000 units of light. what power rating would a CFL need to ...

**maths**

prove that (n-1) squared + n + (n+1)squared = 3n +2

**maths**

prove that 2 2 2 2 (n-1) + n + (n+1) = 3n +2

**chemistry**

what is mantle dynamics?

**physics**

for energy

**physics**

what is the efficiency equation?

**physics**

a 50kg brick bounces with 98% efficiency when droped from a 10 meter ledge. 1.how much energy does it have at the top of the bounce? 2.how high will it bounce?

**physics**

why can't a machine be 100% efficient?

**physics**

a hairdryer turns 250J of electrical energy into 50J of heated air. how efficient is this machine and how much is wasted to sound?

**physics**

a kettle turns 1000j electric energy into 350j of heated water. what is its efficiency? where is the other energy 'wasted' to?

**algebra**

4x-15/2=1/2 2*1/2=1 4x-15=1 4x=1+15 4x= 16 x= 16/4 x= 4

**physics**

ehy can't a machine be 100% efficient?

**english**

why is certification and censorship of films and programmes is necessary? - include children are immpressionable and my copy what they see - children are weak minded - shocks elderly