Fundamentals of Physics-I
Assignment # 1
Topics: Measurement, Vectors, Equations of kinematics, and Motion in 1-dimension
Guidelines for Submission:
1. This is an individual homework assignment.
2. This assignment should be neatly handwritten or may be typewritten.
3. The completed assignments must be scanned and submitted online through SLATE. Only PDF
files are accepted, other formats will be ignored and will not be marked. The due date for online
submission is Sept 23, 2021 (Thursday) by 11:59 PM.
4. Late submission will attract a 10% deduction per day, to a maximum of 30%. Assignments
submitted after 3 days late will be awarded a grade of 0.
5. You are required to show all the steps.
6. You must take care of significant digits and units.
7. Total marks: 25 marks
Q1. Water is poured into a container that has a small leak. The mass m of the water is given as a function
of time t by m = 5.00t0.8 − 3.00t XXXXXXXXXX, with t ≥ 0, m in grams, and t in seconds. (a) At what time is the
water mass greatest, and (b) what is that greatest mass? In kilograms per minute, what is the rate of mass
change at (c) t = 2.00 s and (d) t = 5.00 s? (Hint: Differentiate mass with respect to time) (5 marks)
Q2. The position of a particle moving along the x axis is given in centimeters by x = XXXXXXXXXX50t3, where t is
in seconds. Calculate (a) the average velocity during the time interval t = 2.00 s to t = 3.00 s; (b) the
instantaneous velocity at t = 2.00 s; (c) the instantaneous velocity at t = 3.00 s; (d) the instantaneous velocity
at t = 2.50 s; and (e) the instantaneous velocity when the particle is midway between its positions at t = 2.00
s and t = 3.00 s. Write your final answers in centimeters and seconds XXXXXXXXXXmarks)
Q3. (a) If the position of a particle is given by x = 20t − 5t3, where x is in meters and t is in seconds, when,
if ever, is the particle’s velocity zero? (b) When is its acceleration a zero? (c) For what time range (positive
or negative) is a negative? (d) Positive? XXXXXXXXXXmarks)
Q4. (a) If the maximum acceleration that is tolerable for passengers in a subway train is 1.34 m/s2 and
subway stations are located 806 m apart, what is the maximum speed a subway train can attain between
stations? (b) What is the travel time between stations? (c) If a subway train stops for 20 s at each station,
what is the maximum average speed of the train, from one start-up to the next? (4 marks)
Q5. A rock is thrown vertically upward from ground level at time t = 0. At t = 1.5 s it passes the top of a tall
tower, and 1.0 s later it reaches its maximum height. What is the height of the tower? XXXXXXXXXX3 marks)
Q6 In a meeting of mimes, mime 1 goes through a displacement XXXXXXXXXXˆ ˆ4.0 m i + 5.0 m jd = and mime 2
goes through a displacement XXXXXXXXXXˆ ˆ3.0 m i + 4.0 m jd = − . What are (a) 1 2d d , (b) 1 2d d , (c)
( )1 2 2d d d+  , and (d) the component of 1d along the direction of 2d ? XXXXXXXXXXmarks)