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A transmitter from a researcher's boat sends a signal to the seabed of waves speed 300m/s and it takes 5 seconds for the signal to return back to the boat. Calculate the depth of the sea there.

distance=speed*time

distance=300*5

=1500

1500/2 (as signal travels back and forth)=750m

Answered by Tani A. • Physics tutor

2421 Views

Find two values of k, such that the line y = kx + 2 is tangent to the curve y = x^2 + 4x + 3

There will be intersection when x^2 + 4x + 3 = kx + 2. Our goal is to find the values of k which would only give one solution to this quadratic equation, which would make the lines 'tangent' to each other...

Answered by Andrew N. • Maths tutor

35623 Views

Calculate the kinetic energy of a proton moving at 95% of the speed of light. (c = 3x10^8 m/s, m_p = 1.67x10^-27 kg) [4 marks]

KE = 0.5mv²[1] v = 3x10⁸* 0.95 = 2.85x10⁸[1] KE = 0.5 * 1.67x10^-27* (2.85x10⁸)²[1] KE = 6.782 x10^-11J [1]

Answered by Tom F. • Physics tutor

7192 Views

Assess utilitarianism. (25 Marks).

Assess utilitarianism for a board can be a very open question. You aren't subject to specific forms of the theory, though it can be helpful to assess at least two. Recognising a problem for one i...

Answered by Jack S. • Philosophy tutor

7300 Views

Describe the process of extracellular digestion

Extracellular digestion is a process in which an organism feeds by secreting enzymes through its cell membrane and on to the food. These enzymes then catalyse the breakdown and the digestion of the food. ...

Answered by Stuart N. • Biology tutor

8828 Views