Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

What was the initial speed of a car if its speed is 40ms40\frac{m}{s} after 55 seconds of accelerating at 4ms24\frac{m}{s^2} ?\newlineA. 20ms20\frac{m}{s}\newlineB. 60ms60\frac{m}{s}\newlineC. 10ms10\frac{m}{s}\newlineD. 25ms25\frac{m}{s}\newline

Full solution

Q. What was the initial speed of a car if its speed is 40ms40\frac{m}{s} after 55 seconds of accelerating at 4ms24\frac{m}{s^2} ?\newlineA. 20ms20\frac{m}{s}\newlineB. 60ms60\frac{m}{s}\newlineC. 10ms10\frac{m}{s}\newlineD. 25ms25\frac{m}{s}\newline
  1. Use Formula for Final Velocity: Let's use the formula for final velocity, which is v=u+atv = u + at, where vv is the final velocity, uu is the initial velocity, aa is the acceleration, and tt is the time.
  2. Identify Known Values: We know the final velocity vv is 40m/s40\,\text{m/s}, the acceleration aa is 4m/s24\,\text{m/s}^2, and the time tt is 55 seconds. We need to find the initial velocity uu.
  3. Plug in Values: Plugging the known values into the formula, we get 40m/s=u+(4m/s2×5s)40\,\text{m/s} = u + (4\,\text{m/s}^2 \times 5\,\text{s}).
  4. Calculate Product: Now, we calculate the product of the acceleration and time: 4m/s2×5s=20m/s4 \, \text{m/s}^2 \times 5 \, \text{s} = 20 \, \text{m/s}.
  5. Substitute Values: Substitute the product back into the equation: 40m/s=u+20m/s.40\,\text{m/s} = u + 20\,\text{m/s}.
  6. Solve for Initial Velocity: To find the initial velocity uu, we subtract 20m/s20\,\text{m/s} from both sides of the equation: u=40m/s20m/su = 40\,\text{m/s} - 20\,\text{m/s}.
  7. Final Answer: After the subtraction, we find that the initial velocity uu is 2020 m/s.

More problems from Find derivatives using the quotient rule I