Answer:
It is safer to endure an explosion on land rather than in water. So it is better to take cover on lanad.
Answer: The work done is W = 3528J.
Explanation: Work (W) is an amount of energy used to do determined movement. To calculate it, we use the formula, as the movement is horizontal:
W = F.d, where
F is force on the object
d is distance it went through.
The force acting on the crate is due to friction.
= μ .
μ is the kinetic friction
is the normal force
There is no up and down movement, so , with g = 9.8m/s²
= μ . m . g
= 0.9 . 80 . 9.8
= 705.6 N
Substituing into the work formula, we have:
W = . d
W = 705.6 . 5
W = 3528 J
The work done to move the crate across a distance of 5m is 3528 J.
Answer:
Explanation:
circulatory and digestive. ... An immune response is primarily due to the body's white blood cells recognizing.
Answer: 7.3seconds
Explanation:
Using the echo concept, before echo can occur, we must have an object making the sound (the teacher), the diatance between the object and the reflector (x)(i.e the wall), the time taken for the shadow to disappear (t) and the velocity of sound /movement of the object (v). Using the relationship 2x = vt
According to the question, x = 12m (initial distance), v = speed of object t = time of disappearance.
We have time before disappearance calculated as 2 × 12/1.1 = 21.8s
When he is 4m from the building, it will there take 4 × 21.8/12 = 7.3seconds for his shadow to decrease on the way.