A cheetah is crouched

20m

to the east of an observer (Fig. 2.6a). At time

t=0

the cheetah begins to run due east toward an antelope that is

50m

to the east of the observer. During the first

2.0s

of the attack, the cheetah's coordinate

x

varies with time according to the equation

x=20m+(5.0(m)/(s^(2)))t^(2)

. (a) Find the cheetah's displacement between

t_(1)=1.0s

and

t_(2)=2.0s

. (b) Find its average velocity during that interval. (c) Find its instantaneous velocity at

t_(1)=1.0s

by taking

\\\\Delta t=0.1s

, then

0.01s

, then

0.001s

. (d) Derive an expression for the cheetah's instantaneous velocity as a function of time, and use it to find

v_(x)

at

t=1.0s

and

t=2.0s

.

A cheetah is crouched 20m to the east of an observer (Fig. 2.6a). At time t=0 the cheetah begins to run due east toward an antelope that is 50m to the east of the observer. During the first 2.0s of the attack, the cheetah's coordinate x varies with time according to the equation x=20m+(5.0m/s2)t2. (a) Find the cheetah's displacement between t1=1.0s and t2=2.0s. (b) Find its average velocity during that interval. (c) Find its instantaneous velocity at t1=1.0s by taking t=0.1s, then 0.01s, then 0.001s. (d) Derive an expression for the cheetah's instantaneous velocity as a function of time, and use it to find vx at t=1.0s and t=2.0s