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Olly drove 56 km from A to B. He then drives 61 km from B to C. Olly’s average speed from A to B was 70 km/h. Olly took 75 minutes to drive from B to C. Work out Olly’s average speed for his total drive from A to C.

Key fact: Average speed = total distance/ total timeStep 1: find the time taken for Olly to travel from A to B. Using the formula: time taken = distance travelled / speed(56/70 = 0.8 hrs = 48 mins)Step 2: fi...
SW
Answered by Sacha W. • Maths tutor
12553 Views

F = 5i + 3j. Find the magnitude and direction of F?

i is the unit vector (magnitude of 1) in the direction of the positive x-axis. j is the unit vector in the direction of the positive y-axis. The magnitude of F would be the length of the hypotenuse of a righ...
RI
Answered by Rafiqul I. • Maths tutor
21302 Views

CaCO3 + 2HCl = ?

CaCO 3 is a carbonate and HCl is an acid, so the products will be a salt, water and Carbon Dioxide.Removing 2 Hydrogen atoms and an Oxygen atom for the H 2 O, and one carbon atom and 2 Oxygen atoms for the C...
TG
Answered by Toby G. • Science tutor
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Given the mass number of Aluminium is 27 and the mass number of Oxygen is 16, how many moles of Al2O3 are in 30g? (3 significant figures)

Molar Mass of Al 2 O 3 = 27+27+16+16+16 = 102Mass = mol*Mr so mol = Mass/Mrmol = 30/102 = 0.294117... = 0.294 moles
TG
Answered by Toby G. • Chemistry tutor
3664 Views

Given I climb two steps every second and I have a mass of 50kg, what is the power output of my legs in kilowatts? (3 significant figures)

(There is a diagram showing stairs with steps that are 20cm high) Power = Energy/TimeEnergy required to climb one step = Work Done = Force DistanceForce = Weight = m g = 50 9.81 = 490.5NEnergy = 490.5 0.2 = ...
TG
Answered by Toby G. • Physics tutor
2568 Views