Answer:
Explanation:
Distance and direction of an object's change in position from a starting point. Displacement. 3. Jermaine runs exactly 2 laps around a 400 meter track. What is the displacement? 0 ... David walks 3 km north, and then turns east and walks 4 km. ... A person walks 50 meters directly north, stops, and then travels 32 meters
 
        
             
        
        
        
Answer:
Option B is the correct answer.
Explanation:
Let us consider 40 meter above ground as origin.
Initial velocity = 17 m/s
Final velocity = 24 m/s
Acceleration = 9.81 m/s
We have equation of motion v² = u² + 2as
Substituting
          24² = 17² + 2 x 9.81 x s
            s = 14.63 m
Distance traveled by rock = 14.63 m down.
Height of rock from ground = 40 - 14.63 = 25.37 m = 25.4 m
Option B is the correct answer.
 
        
             
        
        
        
Answer:
T = 74°C
Explanation:
Given Mw = mass of water = 330g, Ma = mass of aluminium = 840g
Cw = 4.2gJ/g°C = specific heat capacity of water and Ca = 0.9J/g°C = specific heat capacity of aluminium 
Initial temperature of water = 100°C.
Initial temperature of aluminium = 29°C
When the boiling water is poured into the aluminum pan, heat is exchanged and after a short time the water and aluminum pan both come to thermal equilibrium at a common temperature T. 
Heat lost by water equal to the heat gained by aluminium pan.
Mw × Cw×(100 –T) = Ma × Ca × (T–29)
330×4.2×(100– T) = 890×0.9×(T–29)
1386(100 – T) = 801(T –29)
1386/801(100 – T) = T – 29
1.73(100 – T) = T – 29
173 –1.73T = T –29
173+29 = T + 1.73T
202 = 2.73T
T = 202/2.73
T = 74°C