# OHara

Popular questions and responses by OHara
1. ## physics

How is dust in operating theatres controlled?

2. ## Physics

A car of mass 550kg accelerates steadily from rest to 25m/s in 30s. a). What is its acceleration? b). What resultant force produces this acceleration? c). The actual force will be greater, why?

3. ## Physics

A student of mass 75kg stands in a lift, what is the normal reaction force(upward force) on him when the lift is accelerating: a). Upwards at 0.65m/s^2 ? b). Downwards at 0.65m/s^2 ?

4. ## Physics

A block measuring 0.1m x 0.4m x 1.5m has a mass of 30kg. Calculate the pressure in each position and state in which position will the block produce greatest and least pressure on the ground.

5. ## Physics - force and pressure

A force of 2000N acts on an area of 4m^2, what is the pressure? What would be the pressure if the same force acted on half the area?

Factorise (x - 1)^2 - 4y^2

7. ## Maths - factorising

Find the quotient and remainder in the following: a) x^4 +3x^3 + 5x^2 - 6x - 8 is divided by x + 2

8. ## Math - Factorising

Find the quotient and the remainder in the following. a). x^4 + 3x^3 + 5x^2 - 6x - 8 is divided by x + 2 b). 2x^4 - 3x^3 + 6x^2 - 5x - 4 is divided by 2x - 3 Please help, this is urgent. Thanks.

9. ## Science

A car of mass 1200kg accelerates from rest at a rate of 2m/s^-2. Calculate how long it should take to reach a velocity of 50m/s.

1. ## Physics

I think I have a little idea on Q.a) only. F = ma = 550 x 25 =13750N so acceleration is a = v - u/t =25 - 0/30 =0.83 ms^-2 that's all i know. I don't know about Q.b and Q.c.

posted on June 7, 2013

Thanks guys:)

posted on June 6, 2013
3. ## Math - Factorising

Thanks kuai.

posted on June 6, 2013
4. ## Maths - factorising

Thanks mate.

posted on June 6, 2013
5. ## Physics

Charles law can be written as: V1/T1 = V2/T2 (at constant pressure)

posted on May 31, 2013
6. ## Science

Thanks Henry.

posted on May 31, 2013