Answer:
網站有中、英文版本,也有繁、簡體版,可通過每頁左上角的連結隨時網站有中、英文版本,也有繁、簡體版,可通過每頁左上角的連結隨時
Explanation:
Answer:
Explanation:
If a particle move with time and expressed according to the formula:
f(t) = 0.01t⁴ − 0.03t³
a) Velocity is the change in motion of the particle with respect to time and it is expressed as;


Hence the velocity of the particle at time t is 
b) To calculate the velocity after 1 second, we will substitute t = 1 into the function v(t) in (a) as shown:

Hence the velocity after 1second is -0.05
c) The particle is at rest when when the time is zero.
Initially, the body is not moving and the time during this time is 0. Hence the particle is at rest when t = 0second
Their momentum is the same.
momentum of dolphin=50kg*16.4m/s=820kg*m/s
momentum of elephant=4100kg*0.20m/s=820kg*m/s
Answer:
5. The 2 features we need to harness the energy from tides are when tides come in and when tides come out.
6. Tidal energy is the most predictable type of renewable energy is because we know the exact locations of the sun and moon all year round.
Answer:
d
Explanation:
a and b: it vibrates in both the difference is whether you hear the sound or not the lack or presence of molecules does not hinder the timing fork from vibrating but can hinder you from hearing since sound is a mechanical wave therefore require a medium bringing us to (c) these vibrations are transmitted because there is presence of a medium i.e air molecules so sound can be heard
but in (c) it is true since the vibrations are created but are not transmitted to your ears due to lack of a medium