Explanation:
Displacement = 5 km
A.
Converting km/h to m/s,
10 km/h * 1000 m/1 km * 1 h/3600 s
= 25/9 m/s
Remember,
700 watt = 700 J/s
Velocity = displacement/time
Time = 5000/(25/9)
= 1800 s
Energy = power * time
= 700 * 1800
= 1,260,000
= 1260 kJ
B.
Converting km/h to m/s,
3 km/h * 1000 m/1 km * 1 h/3600 s
= 5/6 m/s
290 watt = 290 J/s
Velocity = displacement/time
Time = 5000/(5/6)
= 6000 s
Energy = power * time
= 290 * 6000
= 1,740,000
= 1740 kJ
C.
Walking burns more energy; 1,740,000 joules. It burns more because you walk for a greater period of time.
Answer:
Cheetah cubs are in danger from predators like lions and hyenas which can track their prey by scent and so the mother and her cubs leave an area when their scent is too strong so that they are not hunted and the cubs survive.
Mother Cheetahs also train their cubs to hunt so that they may get food for themselves which will ensure their survival as well thus showing that both of these practices can impact on reproductive success.
Answer;
B. Fluorescent lamps operate at a higher temperature than incandescent lamps.
Explanation;
-A fluorescent lamp, is a type of electric light (lamp) that uses ultraviolet emitted by mercury vapor to excite a phosphor, which emits visible light.
-A fluorescent lamp produces less heat, thus, it is much more efficient. A fluorescent bulb can produce between 50 and 100 lumens per watt. This makes fluorescent bulbs four to six times more efficient than incandescent bulbs.
-Fluorescent lamps operate best around room temperature. At much lower or higher temperatures, efficacy decreases.
Complete question:
A train has an initial velocity of 44m/s and an acceleration of -4m/s². calculate its velocity after 10s ?
Answer:
the final velocity of the train is 4 m/s.
Explanation:
Given;
initial velocity of the train, u = 44 m/s
acceleration of the train, a = -4m/s² (the negative sign shows that the train is decelerating)
time of motion, t = 10 s
let the final velocity of the train = v
The final velocity of the train is calculated using the following kinematic equation;
v = u + at
v = 44 + (-4 x 10)
v = 44 - 40
v = 4 m/s
Therefore, the final velocity of the train is 4 m/s.
Answer:
Both are aquatic animals and are hunters
Explanation:
