Dynamics

Question 1

How would you measure the adverge speed over a known distance?

Answer 1

First measure the distance using a trundle wheel, metre stick or measuring tape or any other measuring tool.
Measure the time taken by the car over the distance using a stopwatch/clock or timer.
Calculate the speed by dividing the distance over time.
Repeat if possible.

Formula: d=vt

Question 2

What is the formula for distance?

Answer 2

distance= velocity(speed) x time.

Question 3

What is the formula for speed?

Answer 3

velocity(speed)= distance/time

Question 4

What is the formula for time?

Answer 4

time= distance/ velocity(speed)?

Question 5

How would you measure the instantaneous speed of a car?

Answer 5

To measure instantaneous speed you will need to use electronic timing. A light gate is connected to an a eltronic timer, you would then add a short mask 1-2cm thick card on top of the trolly of vehicle,light cannot pass through the mask. When the front of the mask passes through the light gate, the electronic timer is switched on. When the back of the mask passes throught the light gate the electrionic timer will stop. Then find to find the instantaneous speed you would divide the length of mask by the time on the timer.
formula: instantaneous speed= length of mask/ time on timer.

Question 6

What is the drifference between averge and instantaneous speeds?

Answer 6

averge speed is the speed over a large the distance, the speed might change over that distance where as instantaneous speed is the speed of the vehicle at one point less than a second.

Question 7

Summary of average speed?

Answer 7

The average speed is calculated using the distacnce the object is travelled divided by the time it took. The object may have going faster or slower at points of the journey.

Question 8

Summary of instantaneous speed(v)?

Answer 8

The instantaneous speed(v) of a moving object is its speed at a particular instant of time. The smaller measured time the better estimate for the object’s instananeous speed.

Question 9

Definition of acceleration?

Answer 9

The acceleration (a) or decelerration (negative acceleration) of an object is its change in speed over a given time.

Question 10

What happends when an object is accelerating?

Answer 10

The object’s veleocity(speed) is increasing with time, so each second it is going faster and traveling further.

Question 11

What happens when an object is deceleratting?

Answer 11

The objects veleocity(speed) is increasing with time, so each second it is going slower and covering LESS distance.

Question 12

What does an acceleration of 25ms-2 mean?

Answer 12

The objects speed is increasing by 25 meters per second, every second.

Question 13

What is the unit for acceleration?

Answer 13

The unit for acceleration is meters per second per second (ms-2).

Question 14

Formula for acceleration?

Answer 14

acceleration= change in velocity/ time taken.

a=v-u/t

Question 15

What does V stand for in accelration formula?

Answer 15

final speed

Question 16

What does U stand for in accelration formula?

Answer 16

start speed

Question 17

How would you find the acceleration in a experiment using light gates?

Answer 17

To measure acceleraction of a moving object electronic timing is required.

Two lightgates are connected to an electronic timer/computer.

A mask is fixed on top of the object. Light cannot pass through the mask. When the mask passes through the light gate, no light reaches the light detector.This activates the electronic timer/computer.

The length of the mask is entered into the electric timer/computer.

When the mask on the object passes through the light beam of the top lightgatr, the electronic timer/computer it measures the time it takes then calculates the value for the speed of the mask passing through the light gate(u).

When the mask on top of the object passes through the bottom light gate, the electronic timer/computer it measures the the time it takes, then calculates the speed of the mask passing through.

The electronic timer/computer also records the ime it takes for the mask to travel from the top light to the bottom light gate.