Answer:
t = 2.2 s
Explanation:
Given that,
A person observes a firework display for A safe distance of 0.750 km.
d = 750 m
The speed of sound in air, v = 340 m/s
We need to find the between the person see and hear a firework explosion. let it is t. So, using the formula of speed.
So, the required time is 2.2 seconds.
Answer:
See the answer below
Explanation:
1. Speed is calculated as the ratio of distance and time. Hence, Jame's speed can be calculated as:
400/5 km/hr = 80 km/hr
The unit for the speed would be km/hr. This can also be converted to m/s:
80 km = 80,000 m
1 hr = 3,600 s
80 km/hr = 80,000/3600 m/s = 22.22 m/s
2. Since James drove 400 km in 5 hours, the distance he drove is 400 km.
3. The time it took for James to get there is 5 hours.
If the velocity of the chair is constant, then the net force acting on it is zero.
The force you exert to keep it going is equal and opposite to the force of friction.
Answer:
Because some of the energy is dissipated in the metabolic activities such as digestion and maintaining the warmth of the body of the organism at each level.
Explanation:
Food chain is the sequential chain of energy transfer from one onrgaanism at a trophic level to another organism at the other trophic level. Autotrophs receive the energy from the sun and prepare their own food. Autotrophs then get consumed by the primary heterotrophs and further primary heterotrophs by the secondary heterotrophs. When the secondary heterotrophs die they are then consumed by the scavangers and decayed by the micro-organisms in to the soil which finally help the autotrophs (plants) in their growth.
At each trophic level of the food chain the energy does not gets completely transferred because the organisms also spend some energy in search of the food and the processing of food is also an energy consuming process.
The energy is also used in combating the climatic conditions and predators for the survival.
