A train moving with a speed of 72 km/h applies brakes and comes to a stop in 10 seconds. What is the acceleration of the train?
Practice Questions
1 question
Q1
A train moving with a speed of 72 km/h applies brakes and comes to a stop in 10 seconds. What is the acceleration of the train?
-2 m/s²
-3 m/s²
-4 m/s²
-5 m/s²
First convert speed to m/s: 72 km/h = 20 m/s. Using the formula: acceleration = (final velocity - initial velocity) / time = (0 - 20) / 10 = -2 m/s².
Questions & Step-by-step Solutions
1 item
Q
Q: A train moving with a speed of 72 km/h applies brakes and comes to a stop in 10 seconds. What is the acceleration of the train?
Solution: First convert speed to m/s: 72 km/h = 20 m/s. Using the formula: acceleration = (final velocity - initial velocity) / time = (0 - 20) / 10 = -2 m/s².
Steps: 5
Step 1: Convert the speed of the train from kilometers per hour (km/h) to meters per second (m/s). Use the conversion factor: 1 km/h = 1/3.6 m/s. So, 72 km/h = 72 / 3.6 = 20 m/s.
Step 2: Identify the initial velocity (speed before braking) and the final velocity (speed after stopping). The initial velocity is 20 m/s and the final velocity is 0 m/s.
Step 3: Use the formula for acceleration: acceleration = (final velocity - initial velocity) / time. Here, final velocity = 0 m/s, initial velocity = 20 m/s, and time = 10 seconds.
Step 4: Plug the values into the formula: acceleration = (0 - 20) / 10.
