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Trolley A carrying mass 10kg is moving at speed 5m/s, and collides with stationary Trolley B carrying a mass 5kg. Indicating which Law you would apply, what is the speed and direction of Trolley B if Trolley A's resulting movement is 2m/s to the left?

By the Law of Conservation of Momentum, Initial Momentum=Final Momentum, in a closed system.

Take movement to the right as + and to the left as -

Therefore equate the...

Answered by Parinita S. • Physics tutor

3309 Views

Enzyme inhibitors are often used as antiretroviral drugs in the treatment of HIV. Describe the structure of an enzyme and suggest how antiretroviral drugs would work in the treatment of HIV.

Enzymes are globular (globe-like) proteins, meaning they exist as 3D structures. As a protein, it is composed of a chain of amino acids which is able to fold into secondary structures such as alpha-helice...

Answered by Declan C. • Biology tutor

3245 Views

What are genes and how do work?

Genes are the code that makes up all life on Earth. Genes are sections of the long chain-like molecule called DNA, which is found coiled up into chromosomes in the nucleus of cells. The most important par...

Answered by Anna D. • Biology tutor

2872 Views

Consider the Matrix M (below). Find the determiannt of the matrix M by using; (a) cofactor expansion along the first row, (b) cofactor expansion along the second column

Matrix M is

-2 1 -4

1 -1 5

3 0 2

Let A be a square nxn matrix. Then, for each entry Aij (where 1 </= i < n, 1 </= j < n), the minor of Aij is A(^i;^j), the deter...

Answered by Evi T. • Further Mathematics tutor

3143 Views

Why do ionic compounds like NaCl conduct electricity when dissolved but not when they’re solid, whereas metals conduct electricity when they’re solid?

Firstly, it's important to recognise that ionic compounds and metals are two different structures. Ionic compounds consist of positively charged ions and negatively charged ions held toge...

Answered by Hannah B. • Chemistry tutor

38015 Views