Answer:
The force exerted on the rock by the eruption is, D. 902.5 N
Explanation:
Given data,
The mass of the rock ejected by the volcano, m = 95 kg
The acceleration of the ejected rock, a 9.5 m/s²
The force acting on an object is defined as the product of the mass and its acceleration. It is given by the relation,
F = m x a
= 95 x 9.5
= 902.5 N
Hence, the force exerted on the rock by the eruption is, F = 902.5 N
Complete question is;
Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a sidewalk metabolizes food at the rate of 800 W. (The efficiency of a person shoveling is 3%.)
(a) What is her useful power output? (b) How long will it take her to lift 3000 kg of snow 1.20 m? (This could be the amount of heavy snow on 20 m of footpath.) (c) How much waste heat transfer in kilojoules will she generate in the process?
Answer:
A) P_out = 24 W
B) t = 1470 s
C) Q = 1140.72 KJ
Explanation:
We are given;
Input Power; P_in = 800 W
Efficiency; η = 3% = 0.03
A) Formula for efficiency is;
η = P_out/P_in
Making P_out the subject, we have;
P_out = η•P_in
P_out = 0.03 × 800
P_out = 24 W
B) We know that;
Power = work done/time taken
Thus;
P_out = mgh/t
We are given;
m = 3000 kg
h = 1.20 m
Thus, time is;
t = (3000 × 9.8 × 1.2)/24
t = 1470 s
C) amount of heat wasted is calculated from;
Q = (P_in - P_out)t
Q = (800 - 24) × 1470
Q = 1,140,720 J
Q = 1140.72 KJ
Answer
Procedural bias occurs when the unfair amount of pressure is applied to complete their response quickly.
Measurement bias occurs when there is systematic or random error occur while taking the reading.
Design bias occur when the research fails to encounter all the aspects of the projects before presenting conclusion.
1) The correct answer is option B.
Balance is miscalibrated hence there will be systematic error which is a type of measurement bias.
2) The correct answer is option A.
Limiting response time for participant is an example of Procedural bias.
3) The correct answer is option A
Here, Jackie has not surveyed the diverse group so it is the case of design bias
Answer:222 meters
Explanation:
Speed=80kph=(80x5/18)=(80x5)/18=22.2m/s
Time=10 seconds
distance=speed x time
distance=22.2 x 10
distance=222
distance=222 meters
Resultant force is 400-600=-200N.
-200=60a solve for a.
