Question

An object, initially at rest, accelerates uniformly at 4.5 m/s2 until it obtains a

velocity of 42 m/s. How long does it take to reach the wanted velocity?

Answer 1

To find the time it takes for an object to reach a velocity of 42 m/s when accelerating uniformly at 4.5 m/s², we use the uniform acceleration equation and solve for time to get approximately 9.33 seconds.

Step-by-step explanation:

To determine how long it takes for an object with uniform acceleration to reach a certain velocity, we can use the equation for uniform acceleration, which is:

v = u + at

Where:

• v is the final velocity (42 m/s),
• u is the initial velocity (0 m/s, since the object was initially at rest),
• a is the acceleration (4.5 m/s2),
• t is the time (the unknown we are solving for).

Plugging the values into the equation, we get:

42 m/s = 0 m/s + (4.5 m/s2 × t)

Now, we can solve for t:

42 m/s = 4.5 m/s2 × t

t = (42 m/s) / (4.5 m/s2)

t = 9.33 seconds

Therefore, it takes approximately 9.33 seconds for the object to reach the wanted velocity of 42 m/s.