an antelope moving with constant acceleration covers the distance between two points that are 80 meters apart in 7 seconds. Its velocity as it passes the second point is 15 meters per second.

What is the antelope's velocity at the first point?

What is the acceleration ?

User Icon for Damon Damon answered
16 years ago

say x = 0 at start, t = 0

x = 80 at t = 7
v = 15 at x = 80 and t = 7

v = Vo + a t

x = 0 + Vo t + .5 a t^2

so
15 = Vo + 7 a
80 = Vo (7) +.5 a (49)
solve those two equations for Vo and a

User Icon for ashley ashley answered
16 years ago

could you explain simpler . i get condfused easily im in 10th grade taking 12 grade classes its tough. any help will do

User Icon for Damon Damon answered
16 years ago

ok, you have 2 equations in your physics book for constant acceleration

velocity = initial velocity + acceleration times time
or
v = Vo + a t

position = initial position + initial velocity times time + half of acceleration times time squared
or
x = Xo + Vo t +(1/2) a t^2

here I called Xo, initial position zero and x after 7 seconds was 80
so
80 = 0 + Vo (7) + (1/2) a (7)^2

and I know final velocity at t = 7 is 15 but I do not know Vo
so
15 = Vo + a (7)

User Icon for Observer Observer answered
16 years ago

Obviously, you're in over your head. Maybe you should be taking 10th grade classes.

User Icon for Damon Damon answered
16 years ago

They may have used different letters and so forth, but the equations are there in the book I am sure.

User Icon for Damon Damon answered
16 years ago

ashley got the function stuff ok and we will get this as well.

User Icon for ashley ashley answered
16 years ago

i know this . im doing well i just need a little help

User Icon for ashley ashley answered
16 years ago

thank you damon. i know we will

User Icon for harambe harambe answered
8 years ago

not me

User Icon for Explain Bot Explain Bot answered
11 months ago

To find the antelope's velocity at the first point, we need to use the equation of motion that relates displacement, initial velocity, time, and acceleration.

The equation is:
v = u + at

Where:
v = final velocity
u = initial velocity
a = acceleration
t = time

We are given that the antelope covers a distance of 80 meters in 7 seconds and its velocity at the second point is 15 meters per second.

First, let's calculate the acceleration. We can use the equation:
a = (v - u)/t

Substituting the given values:
a = (15 m/s - u)/7s

Next, to find the antelope's velocity at the first point, we'll use the equation:
80m = ut + (1/2)at^2

Since it starts from rest at the first point, the initial velocity (u) will be 0.

Substituting these values into the equation:
80m = 0 + (1/2)a(7s)^2
80m = (49/2)as^2
160m = 49as^2

Now we have two equations:
a = (15 m/s - u)/7s
160m = 49as^2

To solve these equations, we can substitute the value of a from the first equation into the second equation and solve for u.

160m = 49((15 m/s - u)/7s)s^2
160m = 7s^2(15 m/s - u)
160m = 105s^2 - 7s^2u

Simplifying:
7s^2u = 105s^2 - 160m
u = (105s^2 - 160m)/(7s^2)

Now we can substitute the given values of s and m to find the value of u.

Finally, we have the antelope's velocity at the first point (u) and the acceleration (a).