Answer:
<em>Yes, they are moving in opposite direction one to the other.</em>
Explanation:
Velocity is a vector quantity, which means that it has both magnitude and direction. The magnitude shows the size of the velocity, and the direction shows which way it is moving in reference to a chosen reference direction. If the red box is assigned a positive velocity, and the blue box is assigned a negative velocity, as indicated in the question, then it means that the red box, and the blue box, both move in opposite direction to the other.
Acceleration=Final velocity-Initial velocity /time.
Acceleration=a=4m/s².
Initial velocity= u= 44m/s
Final velocity=v= let it be v, since we are to look for the final velocity.
Time=t=10seconds.
Mathematically:
a=v-u/t
Substituting the givens into the equation.
4=v-44/10
cross multiply.
4×10 = v-44
40=v-44
40+44=v
v=84m/s
Answer:
171.5Watts
Explanation:
Given parameters:
Mass = 5kg
Distance = 28m
Time = 8s
Unknown:
Power = ?
Solution:
Power is the rate at which work is done;
Power = 
Work done = force x distance = mg x d =
m is the mass
g is the acceleration due to gravity
d is the distance
Work done = 5 x 9.8 x 28 = 1372J
Power = 
= 171.5Watts
Answer:
462000J
Explanation:
Quantity of heat= mass x specific heat capacity of iron x change in temp
specific heat capacity of iron is 462J/Kg/K
change in temp = 250-50= 200°C
200°C is equivalent to 200K since 1°C is 1K
Q= mct
= 5x462x200
= 462000J
