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How is ATP used in myofibril contraction?

ATP is bound to the myosin head to cause detachment of the head from the actin filament, the ATP is then hydrolysed and as a result the myosin head reattaches to the actin filament. The now hydrolysed ATP...

Answered by Sam W. • Biology tutor

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theta = arctan(5x/2). Using implicit differentiation, find d theta/dx.

First, we must rearrange to give 2tan(θ) = 5x. Differentiate both sides with respect to x: 2sec²(θ)dθ/dx = 5 Use identity sin²(θ) + cos²(θ) = 1, dividing through by cos

Answered by Callum W. • Maths tutor

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Explain why chlorine has a lower boiling point than Bromine. (2 marks)

Chlorine molecules are smaller than bromine molecules in size, therefore, the van der Waals forces (intermolecular forces) are weaker between Cl2 molecules than compared to Br2 molecules.

Answered by Joseph B. • Chemistry tutor

12474 Views

A cylindrical rod of radius 7mm and Young’s Modulus 70 GPa has a weight F applied to it. The material experiences a strain of 0.2%. What force has been applied?

Young's Modulus is defined as the ratio of stress to strain. E = stress/strain. Stress is the force per unit area, F/A. By substitution, we can see that E = F/(A x strain). Rearranging gives F = E x A x s...

Answered by Callum W. • Physics tutor

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