2023 paper 1

Explain the effect on the distance required to bring a vehicle to rest if the road has an upwards slope (2)

Using forces

there is additional backwards force or greater resultant force down the slope

A smaller distance is required to do the same work

or transfer the same quantity of KE

Determine the value of g

Method 1. Vertical drop

Method 2. Rolling ball

Vertical drop: height = 1.20m Time taken = 0.5

Rolling ball: length of ramp= 1.900m Angle= 30 Time taken = 0.9

Compare and discuss the uncertainties of the two values of g that could be obtained, Describe how the student would analyse both sets of data when a full range of results has been taken

Uncertainty: no repeats makes the experiment inherently uncertain

Height ± 1cm

Resolution/ precision of the stopclock is 0.01s, reaction time is much greater

Comparison: ramp method has greater time and length, so smaller percentage uncertainty

Friction affects the ramp method

Analysis: finding from s= ½ at² for multiple values of s and average

Appropriate graph plotter- t² on y axis, s on x axis

Describe how to find the centre of mass of a 2D shape, including any equipment required

Suspend object (freely) and mark vertical (down)

Repeat(s) (from different point) and reference to

intersection of verticals

Plumb line/ plumb bob /AW

A bridge with a moving section 14m long and has a weight of 120kN

The center of mass of the structure is 6.3m away from the pivot

Calculate the average power required to raise the bridge to a vertical position in 90s.

P = Work done / time

= 120kN × 6.3 + 1.3 ÷ 90

= 10100 W

A wire of cross-sectional area 3.9 × 10^-6 m²2 and carried a load of 240N

The strain of the wire is 0.30%

Which value of the Young modulus in Pa, is correct

A. 2.05 × 10^8

B. 2.1 × 10^8

C. 2.05 × 10^10

D. 2.1 × 10^10

D.

Force/ area

During cold weather salt is spread on roads causing ice to melt without changing its temperature

Which statement correctly describes the energy of water particles during this process?

A. Potential and kinetic energies decrease

B. No energy changes occur

C. Only kinetic energy increases

D. Only potential energy increases

D

Explain what the weight for air displaced by an object has the same magnitude as the object (and its contents)

Upthrust = weight of fluid or air displaced

Airship in equilibrium/resultant force is 0 so

upthrust = weight of the airship

The pressure of helium in a gas bag is maintained at a value only slightly greater than atmospheric pressure.

Suggest why a larger pressure is not used.

●(Greater pressure) would increase the

density/mass/weight of the helium

● (increased pressure but) no change in

volume therefore no more upthrust.