1.
Explain whether or not the following particles have an
acceleration:
(i) a particle moving in a straight line with constant
speed, and
(ii) a particle moving on a curve with constant speed
2.
Consider the following combination of signs and values,
for velocity and acceleration of an object with respect
to a one-dimensional motion along x-axis:
|
Velocity
|
Acceleration
|
Velocity
|
Acceleration
|
|
a.
Positive
|
Positive
|
e.
Negative
|
Negative
|
|
b
Positive.
|
Negative
|
f.
Negative
|
Zero
|
|
c.
Positive
|
Zero
|
g.
Zero
|
Positive
|
|
d.
Negative
|
Positive
|
h.
Zero
|
Negative
|
Describe
what an object is doing in each case, and give a real-life
example for a car on an east-west one-dimensional axis,
with east considered as the positive direction.
3.
A car travelling initally at + 7.0 m/s accelerates at
the rate of + 0.80 m/s2 for an interval of
2.0s. What is its velocity at the end of the acceleration?
4.
A car travelling in a straight line has a velocity of
+ 5.0 m/s at some instant. After 4.0s, its velocity is
+ 8.0 m/s. What is its average acceleration in this time
interval?
5.
The velocity - time graph for an object moving along a
straight line as shown in figure. 7.10.
Find
the average acceleration of this object during the time
intervals 0 to 5.0 s, 5.0s to 15.0s, and 0 to 20.0s.
