Questions: If an object is projected upward with an initial velocity of 123 ft per sec, its height h after t seconds is h=-16t^2+123t. Find the height of the object after 4 seconds.
The height of the object after 4 seconds is ft.
Transcript text: If an object is projected upward with an initial velocity of 123 ft per sec , its height $h$ after $t$ seconds is $h=-16 \mathrm{t}^{2}+123 \mathrm{t}$. Find the height of the object after 4 seconds.
The height of the object after 4 seconds is $\square$ ft.
Solution
Solution Steps
Step 1: Understand the Problem
We are given the height function of an object projected upward:
\[ h(t) = -16t^2 + 123t \]
We need to find the height of the object after 4 seconds.
Step 2: Substitute the Time into the Height Function
Substitute \( t = 4 \) into the height function:
\[ h(4) = -16(4)^2 + 123(4) \]
Step 3: Calculate the Height
First, calculate \( 4^2 \):
\[ 4^2 = 16 \]
Now substitute back into the equation:
\[ h(4) = -16(16) + 123(4) \]