Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts

2018 WAEC Physics Theory  (a) Define uniform acceleration. (b) Forces act on a car in motion. List the (i)...

Physics
WAEC 2018

 (a) Define uniform acceleration.

(b) Forces act on a car in motion. List the

(i) horizontal forces and their directions;

(ii) vertical forces and their directions

(c) A car starts from rest and accelerates uniformly for 20s to attain a speed of 25 ms\(^{-1}\). It maintains this speed for 30s before decelerating uniformly to rest. The total time for the journey is 60 seconds.

(i) Sketch a velocity-time graph for the motion.

(ii) Use the graph to determine the (\(\alpha\)) total distance travelled by the car (\(\beta\)) deceleration of the car.

The figure above illustrates a force-extension graph for a stretched spiral spring. Determine the work done on the spring.  SEE THE DIAGRAM ABOVE

WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post UTME Past Questions Agent
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Explanation

(a) Uniform acceleration is the constant time rate of increase in velocity.

(b) (i) Horizontal Force;

Forward force - Thrust

backward force - Frictional force

(ii) Vertical Force

Upward force - Normal reaction.

Downward force - Weight of the car.

 

(c) SEE THE DIAGRAM ABOVE.

 

 

 

 

(ii) (\(\lambda\)) Total distance

= Area of trapezium OABC

= \(\frac{1}{2}\)[AB + OC] AD

= \(\frac{1}{2}\)[60+30] x 25

=1125m

(\(\beta\)) Deceleration = slope of BC

= \(\frac{BE}{CE} = \frac{25}{10}\) 

= 25m/s\(^2\)


(d) Work done = \(\frac{1}{2}\)Fe
= \(\frac{1}{2}\) x 12 x \(\frac{0.5}{100}\)J

= 0.03J


Report an Error Ask A Question Download App
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Your School's Whatsapp Group - Join Us now
Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now