A particle is moving across a perfectly smooth horizontal surface at a constant velocity. It is acted upon by exactly two constant horizontal forces.
The first force is F1=(250i−120j) N\mathbf{F}_1 = (250\mathbf{i} - 120\mathbf{j})\text{ N}F1=(250i−120j) N.
The second force is F2=(ki+120j) N\mathbf{F}_2 = (k\mathbf{i} + 120\mathbf{j})\text{ N}F2=(ki+120j) N.
Find the value of kkk.
Select your answer from the following:
−250-250−250
−130-130−130
130130130
250250250
139 exam-style questions on AQA A Level Maths 3.3 R: Forces and Newton's laws, covering 3.3.1 Concept of a force and Newton's first law, 3.3.2 Newton's second law, 3.3.3 Weight and motion under gravity, 3.3.4 Newton's third law and equilibrium, 3.3.5 Addition of forces and resultants (A-level only), and 3.3.6 Friction (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.