Math Problem Statement

A ball is thrown straight downward with a speed of 0.50 meter per second from a height of 4.0 meters. What is the speed of the ball 0.70 second after it is released? [Neglect friction.]

10 points 0.50 m/s 7.4 m/s 9.8 m/s 15 m/s

Solution

To solve this problem, we will use the kinematic equation for uniformly accelerated motion, as gravity is the only force acting on the ball (neglecting friction). The equation we will use is:

v=v0+atv = v_0 + at

where:

  • vv is the final velocity,
  • v0=0.50m/sv_0 = 0.50 \, \text{m/s} is the initial velocity (speed at the moment the ball is released),
  • a=9.8m/s2a = 9.8 \, \text{m/s}^2 is the acceleration due to gravity,
  • t=0.70secondst = 0.70 \, \text{seconds} is the time after the ball is released.

Now, plug in the values:

v=0.50m/s+(9.8m/s2)(0.70s)v = 0.50 \, \text{m/s} + (9.8 \, \text{m/s}^2)(0.70 \, \text{s})

v=0.50m/s+6.86m/sv = 0.50 \, \text{m/s} + 6.86 \, \text{m/s}

v=7.36m/sv = 7.36 \, \text{m/s}

Rounding to two significant figures (as in the given data), we get:

v7.4m/sv \approx 7.4 \, \text{m/s}

Thus, the speed of the ball 0.70 seconds after it is released is 7.4 m/s.

Answer: 7.4 m/s


Would you like more details or have any further questions on this?

Here are some additional related questions:

  1. What would be the velocity if the ball were thrown upwards instead?
  2. How long would it take for the ball to hit the ground if thrown from the same height?
  3. What is the displacement of the ball after 0.70 seconds?
  4. How would air resistance affect the result if it were not neglected?
  5. How does the mass of the ball affect its motion under gravity?

Tip: Remember, when dealing with gravity near Earth's surface, the acceleration due to gravity is always approximately 9.8m/s29.8 \, \text{m/s}^2.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Kinematics
Linear Motion
Acceleration due to Gravity

Formulas

v = v0 + at

Theorems

Uniformly Accelerated Motion

Suitable Grade Level

Grades 9-12