Answer:
(a) Most reactive 
Metal B
Metal D
Metal A
Least reactive Metal C
(b) (i) Bubbles should form very slowly
(ii) No reaction takes place
Explanation:
(a) The given metals arranged in their order of reactivity are;
Most reactive Metal B
Metal D
Metal A
Least reactive Metal C
The other of reactivity is based on the nature of their reactivity of the metals in air
(b) (i) Based on the reactivity of the metals in air, whereby metal A reacts very slowly and an oxide is formed, we have that, based on the reactivity of the metal A, when mixed with dilute hydrochloric acid, bubbles should form very slowly
(ii) Similarly, given that metal C is unreactive, we have that when small pieces of metal C are added to dilute hydrochloric acid, no reaction takes place.
Answer:
Option D
490 J
Explanation:
When at a height of 100 am above and released, the ball initially posses only potential energy. When it falls, some potential energy is converted to kinetic energy.
Initial potential energy= mgh where m is the mass, g is the acceleration due to gravity and h is height. Substituting 1 Kg for m, 9.81 for g and 100 m for h then
PE initial = 1*9.81*100= 981 J
At 50 m, PE will be 1*9.81*50=490.5 J
Subtracting PE at 50 m from initial PE we get the energy that has been converted to kinetic energy hence
981-490.5= 490.5 J
Approximately, 490 J
We will first convert lb to grams and in³ to milliliters.
350 lb : 2.205 = 158.75733 kg = 158,757.33 grams
1.3 · 10^4 in³ = 13,000 in³ = 13,000 · 0.016387064 = 213.031 liters
213.031 liters · 1,000 = 213,031 milliliters
Density = m / V = 158,753.33 g / 213,031 ml = 0.7452 g/ ml
Answer: A block of material will float.
We are given with two measurements of the arm and an input weight. To answer this problem,we need to balance the forces and use the lengths of the arms.
209 N * 8 m = x * 1.5 m
x = 1114.67 N
it takes 1114.67 N to lift the input weight
<u><em>In accordance with the International Regulation for the prevention of collisions at sea</em></u><u>:
</u>
<u>1.- A sailing boat has a passing preference over a motorized boat, </u><u>except when the motor boat is limited by its draft</u><u>.
</u>
<u>2.- The sailboat must maintain its course and speed.
</u>
<u>3.- </u><em><u>If it is evident that the PWC does not respond</u></em><u>, the sailboat must sound the warning signal, and change its course to starboard.
</u>
<u>4.- </u><u><em>All actions must be taken as soon as possible</em></u><u>.
</u>
<u>5.- If a sailboat is using its engine, the situation changes, and in that case, both ships must alter to starboard.</u>
