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Expand and simplify 3(m + 4) – 2(4m + 1)

The first thing that we are going to do to tackle this problem is to expand the bracket on the left-hand side (3(m+4)). To do this you have to multiply each of the terms inside the bracket with the 3 that is...
RR
Answered by Rahee R. • Maths tutor
4987 Views

The energy transferred from the water in the kettle to its surroundings in 2 hours is 46 200 J. The mass of water in the kettle is 0.50 kg. The specific heat capacity of water is 4200 J/kg °C. What is its temperature after 2 hours?

The water loses 4200 J/kg °C * 0.5 kg = 2100 J/°C As it's lost 46,200 J in total (regardless of the time it took for this to happen), it must have reduced in temperature by 46,200 J / 2100 J/°C = 22°C. Assum...
DB
Answered by Dewi B. • Physics tutor
27425 Views

1) 3x + y = 11 2) 2x + y = 8

Subtract 2) from 1), we get x = 3. This means that y must be 2.
DB
Answered by Dewi B. • Maths tutor
3729 Views

Explanation of alpha scattering experiment

Alpha particles which are made up of 2 protons and 2 neutrons (overall positive charge) are fired towards a thin sheet of gold. To ensure any deflection of the alpha particles is only due to the gold sheet t...
JM
Answered by James M. • Physics tutor
20829 Views

Write √98+3√8-√200 in the form a√2, where a is an integer

Step 1 : Put all the surds in to the form a√2. Starting with √98 try and work out what numbers multiply together with 2 to get 98 (2x49). Therefore √98=√(2x49). As 49 is a square number you can take it outsi...
ER
Answered by Emma R. • Maths tutor
6581 Views