Question

Supersonic jet flew 2,200 m after experiencing a uniform acceleration of 3.0 m/s^2. If it achieved a top speed of 505 m/s, then what was its initial speed?

a) 490 m/s
b) 485 m/s
c) 480 m/s
d) 475 m/s

Answer 1

The initial speed of the supersonic jet was calculated using the kinematic equation, which resulted in an initial speed of approximately 491.75 m/s, making option (a) 490 m/s the closest answer choice.

Step-by-step explanation:

To find the initial speed of the supersonic jet, we can use the kinematic equation that relates initial velocity, final velocity, acceleration, and displacement without involving time. The equation we'll use is:

v2 = u2 + 2as

Where:
v is the final velocity,
u is the initial velocity,
a is the acceleration, and
s is the displacement.

We know that the final velocity v = 505 m/s, acceleration a = 3.0 m/s2, and displacement s = 2200 m. So we need to solve for u:

5052 = u2 + 2 × 3 × 2200

After rearranging and solving for u:

u2 = 5052 - 2 × 3 × 2200

u = √(255025 - 13200)

u = √(241825)

u = 491.75 m/s

Thus, the closest answer choice to the initial speed is (a) 490 m/s.