# math

A body moves in a straight line so that its distance 'x' from a fixed point after 't' seconds is given by the formula x=9t^2÷2-t^3÷2 find: a; its velocity after 2 seconds b; its velocity when the acceleration is 0???

1. 👍 0
2. 👎 0
3. 👁 212
1. x(t) = 9t^2/2 - t^3/2
v(t) = 9t - 3t^2/2
a(t) = -3t

Now it should be easy to answer the questions.

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Physics

A runner is jogging in a straight line at a steady vr= 2.2 km/hr. When the runner is L= 4 km from the ﬁnish line, a bird begins ﬂying straight from the runner to the ﬁnish line at vb= 6.6 km/hr (3 times as fast as the

2. ### math

Draw a line that goes through point B. Draw a line that intersects the first line, but not at point B. Measure the distance of point B to the intersection. On the second line, draw point B′ that is the same distance from the

3. ### Physics

Two cars, A and B, travel in a straight line. The distance of A from the starting point is given as a function of time by xA(t)=αt+βt^2, with α=2.60m/s and β=1.20m/s^2. The distance of B from the starting point is

4. ### Physics

A runner is jogging in a straight line at a steady vr= 2.1 km/hr. When the runner is L= 4.4 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 10.5 km/hr (5 times as fast as the

1. ### network analysis

Point A and B are 0.1m apart. A Point charge of +3.0*10^-9 c is placed at A and a point charge at -1.0*10^-9c B. X is the point on the straight line between A and B where the electric potential is zero. calculate the distance AX

2. ### Physics

A runner is jogging in a straight line at a steady vr= 6.8 km/hr. When the runner is L= 2.2 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 20.4 km/hr (3 times as fast as the

3. ### physics

A runner is jogging in a straight line at a steady vr= 7.5 km/hr. When the runner is L= 6.3 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 22.5 km/hr (3 times as fast as the

4. ### Physics

A runner is jogging in a straight line at a steady vr= 5 km/hr. When the runner is L= 7.1 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 15 km/hr (3 times as fast as the runner).

1. ### Physics

Two very long, straight, parallel wires separated by distance d carry currents of magnitude I in opposite directions. Find the magnetic field at a point equidistant from the lines, with a distance 2d from each line.

2. ### Physics

A runner is jogging in a straight line at a steady vr= 3.1 km/hr. When the runner is L= 6.1 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 18.6 km/hr (6 times as fast as the

3. ### Physics

Q1: A runner is jogging in a straight line at a steady vr= 6.8 km/hr. When the runner is L= 2.4 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 13.6 km/hr (2 times as fast as the

4. ### Physics

A runner is jogging in a straight line at a steady vr =5 km/hr.When the runner is L= 6.2 km from the finish line, a bird begins flying straight from the runner to the finish line at vb=15 km/hr (3 times as fast as the runner).