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Outline and explain the psychodynamic approach in psychology

The psychodynamic approach looks at the unconscious basis of behaviour. According to Freud, the personality is split into 3 parts: the ID satisfies selfish needs; the superego satisfies moral needs and th...

Answered by Daisy R. • Psychology tutor

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Explain How Macrophage becomes an Antigen presenting cell

Phagocytosis occurs:The Macrophage surrounds and envelops the pathogen with pseudopodia The pseudopodia envelops the bacteria completely forming a vesicle, called a phagosomephagosome is fused with a lyso...

Answered by Ibtihaj C. • Biology tutor

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What is protein Structure

Protiens are polymer of amino acidsAmino acids are joined by peptide bondsPeptide bonds are formed by condensation4 different structures Primary structure is sequence of amino acids held together by pepti...

Answered by Victoria W. • Biology tutor

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A projectile is launched from ground level with a speed of 25 m/s at an angle of 42° to the horizontal. What is the horizontal distance from the starting point of the projectile when it hits the ground?

Resolve the vertical velocity of the projectile (25sin42) and use v=u+at where v=-25sin42m/s, u=25sin42m/s, a=-9.8m/s/s to find t. t= (50sin42)/9.8= 3.41sResolve horizontal velocity (25cos42) and multiply...

Answered by Joe W. • Physics tutor

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Write 5cos(theta) – 2sin(theta) in the form Rcos(theta + alpha), where R and alpha are constants, R > 0 and 0 <=alpha < 2 π Give the exact value of R and give the value of alpha in radians to 3 decimal places.

Use the formula cos(A+B)=cosAcosB-sinAsinB, Rcos(theta+alpha)=Rcos(alpha)cos(theta)-Rsin(alpha)sin(theta)5=Rcos(alpha)2=Rsin(alpha)tan(alpha)=2/5alpha= 0.381R=sqrt(5^2+2^2)=sqrt(29)So, 5cos(theta) – 2sin(...

Answered by Joe W. • Maths tutor

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