Math Problem Statement

an object is moving in the xy plane at t=1s the object's velocity is 3 m/s in the +x direction at t=2s the object's velocity is 4 m/s in the +y direction. what is the average accrleration of the object between t=1s and t=2s

Solution

To find the average acceleration of the object, we need to use the formula for average acceleration:

aavg=v2v1t2t1\vec{a}_{avg} = \frac{\vec{v}_2 - \vec{v}_1}{t_2 - t_1}

Where:

  • aavg\vec{a}_{avg} is the average acceleration vector,
  • v1\vec{v}_1 and v2\vec{v}_2 are the velocity vectors at times t1t_1 and t2t_2,
  • t1=1st_1 = 1 \, \text{s},
  • t2=2st_2 = 2 \, \text{s},
  • v1=3m/si^\vec{v}_1 = 3 \, \text{m/s} \, \hat{i} (velocity in the +x direction),
  • v2=4m/sj^\vec{v}_2 = 4 \, \text{m/s} \, \hat{j} (velocity in the +y direction).

Now let's break down the change in velocity:

  1. The velocity at t1=1st_1 = 1 \, \text{s} is v1=3i^+0j^m/s\vec{v}_1 = 3 \, \hat{i} + 0 \, \hat{j} \, \text{m/s}.
  2. The velocity at t2=2st_2 = 2 \, \text{s} is v2=0i^+4j^m/s\vec{v}_2 = 0 \, \hat{i} + 4 \, \hat{j} \, \text{m/s}.

The change in velocity is: Δv=v2v1=(0i^+4j^)(3i^+0j^)\Delta \vec{v} = \vec{v}_2 - \vec{v}_1 = (0 \, \hat{i} + 4 \, \hat{j}) - (3 \, \hat{i} + 0 \, \hat{j}) Δv=3i^+4j^m/s\Delta \vec{v} = -3 \, \hat{i} + 4 \, \hat{j} \, \text{m/s}

The time interval is: Δt=t2t1=2s1s=1s\Delta t = t_2 - t_1 = 2 \, \text{s} - 1 \, \text{s} = 1 \, \text{s}

Now, the average acceleration is: aavg=ΔvΔt=3i^+4j^1s=3i^+4j^m/s2\vec{a}_{avg} = \frac{\Delta \vec{v}}{\Delta t} = \frac{-3 \, \hat{i} + 4 \, \hat{j}}{1 \, \text{s}} = -3 \, \hat{i} + 4 \, \hat{j} \, \text{m/s}^2

Thus, the average acceleration is: aavg=3i^+4j^m/s2\vec{a}_{avg} = -3 \, \hat{i} + 4 \, \hat{j} \, \text{m/s}^2

In magnitude, the average acceleration can be found as: aavg=(3)2+42=9+16=25=5m/s2|\vec{a}_{avg}| = \sqrt{(-3)^2 + 4^2} = \sqrt{9 + 16} = \sqrt{25} = 5 \, \text{m/s}^2

So the magnitude of the average acceleration is 5m/s25 \, \text{m/s}^2, and the direction is in the quadrant where the acceleration is negative in the xx-direction and positive in the yy-direction.

Would you like a detailed breakdown of any part of this solution?

Here are 5 related questions:

  1. How is the direction of acceleration determined in 2D motion?
  2. What happens if the velocity changes both in magnitude and direction?
  3. How does the average acceleration differ from instantaneous acceleration?
  4. How do we calculate the magnitude of a vector from its components?
  5. How would the result change if the velocity at t=2st=2s had components in both xx and yy?

Tip: The average acceleration only depends on the initial and final velocities, not on the path the object takes in between.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Kinematics
Vector Operations
2D Motion

Formulas

Average acceleration formula: a_avg = (v2 - v1) / (t2 - t1)
Magnitude of vector: |a| = sqrt(a_x^2 + a_y^2)

Theorems

-

Suitable Grade Level

Grades 10-12