An underwater robotic exploration vehicle (ROV) is traveling horizontally along the seabed.
The acceleration of the ROV is 0.8 m/s20.8\text{ m/s}^20.8 m/s2.
The mass of the ROV is 65 kg65\text{ kg}65 kg.
(i) State the equation linking force, mass and acceleration.
(ii) Calculate the force needed to produce this acceleration.
(iii) Suggest a reason why the forward thrust force exerted by the propulsion system of the ROV must be greater than the calculated force.
The ROV starts from rest and accelerates at 0.8 m/s20.8\text{ m/s}^20.8 m/s2 until its velocity is 3.6 m/s3.6\text{ m/s}3.6 m/s.
(i) State the relationship between acceleration, change in velocity, and time taken.
(ii) Show that the time taken to reach 3.6 m/s3.6\text{ m/s}3.6 m/s is 4.5 s4.5\text{ s}4.5 s.
The velocity-time graph below shows the motion of the ROV during a different part of its mission.
(i) Calculate the distance travelled by the ROV.
(ii) State the equation linking average speed, distance moved and time taken.
(iii) Calculate the average speed of the ROV for the whole journey.
