WAEC GCE PHYSICS ANSWERS 2020

Here is the waec gce physics answers for 2020, please share to your friends and good luck.

PART I

ANSWER FIVE (5) ONLY.

(1)

(i)They are use to find the unit of a given physical quantity in a given system of units.

(ii)They are use to find dimensions of physical constants or coefficients.

(iii)They are use to convert a physical quantity from one system of units to another.

(2a)

Time of flight: Time of flight (T) is the time required for a projectile to return to the Same level from which it was projected

T= 2usin θ / g

(2b)

Maximum height: Maximum height(H) is the highest vertical distance attained as measured from the horizontal projectile plane.

H = U²sin²θ / 2g

(2c)

Range : Range(R) is defined as the horizontal distance from the point of projection to the point where the projectile hits the projection plane again

R= U²sin2θ / g

(7a)

Magnetic materials are materials studied and used mainly for their magnetic properties. The magnetic response of a materials is largely determined by the magnetic dipole moment associated with the intrinsic angular momentum, or spin, of its electrons.

(7b)

(i)by heating past the Curie point

(ii)by applying a strong magnetic field

PART II

ANSWER 3 ONLY.

(11ai)

Reactance is the opposition of a circuit element to the flow of current due to that element’s inductance or capacitance.

(11aii)

Impedance is measure of the opposition to the flow of alternating current through a circuit

(9ai)

Heat describes the transfer of thermal energy between molecules within a system and is measured in Joules. Heat measures how energy moves or flows. … Temperature describes the average kinetic energy of molecules within a material or system and is measured in Celsius (°C), Kelvin(K), Fahrenheit (°F), or Rankine (R).

(9aii)

The lower fixed point, or ice point, is the temperature of pure melting ice at normal atmospheric pressure. While The upper fixed point, is the temperature of pure boiling water at normal atmospheric pressure.

11ai) Reactance is the opposition of a circuit element to the flow of current due to that element’s inductance or capacitance.10bi) The principle of superposition says: When two or more waves cross at a point, the displacement at that point is equal to the sum of the displacements of the individual waves. The individual wave displacements may be positive or negative. If the displacements are vectors, then the sum is calculated by vector addition.*Number 9c*

 Linear expansivity is the fractional increase in length of a specimen of a solid, per unit rise in temperature. If a specimen increases in length from l1 to l2 when its temperature is raised θ°, then the expansivity (α) is given by: l2 = l1(1 + αθ).*PHYSICS* 

8ai.. In physics, work is the energy transferred to or from an object via the application of force along a displacement. … A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.

 8b 

Kinetic friction is defined as a force that acts between moving surfaces. A body moving on the surface experiences a force in the opposite direction of its movement. The magnitude of the force will depend on the coefficient of kinetic friction between the two material..11bi) *The sources must be coherent 

*must have a single *PHYSICS* 

8ai.. In physics, work is the energy transferred to or from an object via the application of force along a displacement. … A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.

 8b 

Kinetic friction is defined as a force that acts between moving surfaces. A body moving on the surface experiences a force in the opposite direction of its movement. The magnitude of the force will depend on the coefficient of kinetic friction between the two material.

cheers…