Higher Physics Checklist To Date1. Errors booklet questions 1 - 6 in problem jotter

(blue)2. “Adding Vectors” Tutorial 1 in problem jotter.

(This tutorial can be found in the homework booklet and a pdf file of the answers is also attached here)

3. Unit 1 Problems 14 - 22 on Adding Vectors, in problem jotter.

4. HOMEWORK 1 (1995 Past Paper Q1 handout) - should be done in RED HW jotter and submitted for marking.

5. Unit 1 Problems 23 - 26 on Resolving Vectors, in problem jotter.

6. “Resolving Vectors” Tutorial 2 (Q.1 & 2) in problem jotter.(This tutorial can be found in the homework booklet and a pdf file of the answers is also attached here)

Resolving Vectors (recap)

Components of a Vector

Any single vector can be split into 2 vectors at right angles to each other.

Eg)

Resolving Vectors

Components of a Vector

Any single vector can be split into 2 vectors at right angles to each other.

Eg)

Resolving Vectors

Components of a Vector

Any single vector can be split into 2 vectors at right angles to each other.

Eg)

Objects on a Slope

If an object accelerates in some direction, then the force making it accelerate must be in the same direction.

For example, a mass (m) on a frictionless slope which makes an angle, , with the horizontal …

m

NOTES p.6

m

The force acting on the mass is “gravity” which is the downwards “weight” of the mass … W = mg.

W = weight in Newtons (N) m = mass in kg g = gravitational field strength in N/kg)

W = mg

`

m

BUT the force affecting the motion of the mass on the slope is the DOWNSLOPE COMPONENT OF WEIGHT.

W = mg

mg(perpendicular

component)

So …

Downslope component of weight = opp = hyp sin = mg sin

(perpendicular comp. = mg cos)

2kg

Example

A 2kg mass is released on a slope which makes a 30o angle with the ground. A frictional force of 4N acts upslope. Calculate the acceleration of the mass.

mg sin

4N

2kgmg sin

4N

1st downslope weight = mg sin

= 2 x 9.8 x sin 30

= 9.8N

2nd unbalanced force = FR = 9.8N – 4N

= 5.8N, downslope

3rd Fu = 5.8N, downslope

m = 2 kg

a = ?

a = Fu / m

= 5.8 / 2

= 2.9 m/s2, downslope

So far, the following “Vectors” questions should be completed

Tutorial 1 (all)

Tutorial 2 (all)

Problems 14 – 22 (addition of vectors)

Problems 23 – 26 (resolving vectors)

+

Homework 1995 Past Paper Q1

Tutorial 1

1.a) 9.9N, 4.95 ms-2 3. a) 4.47ms-1 @ 333o b) 4ms-1 @ 030o

4.a) b) 20.5ms-1 @ 73o from the horizontal

Tutorial 2

1a) H – 18.8 ms-1, V – 6.8 ms-1 c) H – 17.7 ms-1, V – 17.7 ms-1

e) H – 0 ms-1, V – 30 ms-1 2. a) 346N b) 230N c) 11N d) 7.9N

e) 3.46N f) 13.8N 3.a)(i) 0.02ms-2 ii) 1.35ms-2 iii) 2.14ms-

2

iv) 1.54ms-2 v) 5.05ms-2 b) 19.9o

Problems 14 – 22 (addition of vectors)

Problems 23 – 26 (resolving vectors)

Tutorial 2 - see HW booklet

Tutorial 1 see HW booklet