0.67s
Explanation:
Given parameters:
Speed of bullet = 600m/s
Distance of target = 400m
Unknown:
Time taken for bullet to reach target = ?
Solution:
Speed is a physical quantity that expresses the rate of change of distance with time;
Speed = 
Since time is unknown, we make it the subject of the expression;
time =
= 
time = 0.67s
Learn more:
Speed brainly.com/question/10048445
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Answer:
(a)
(b) 
Explanation:
Part (a)
The total length of copper cord L=86.3 m
The cross sectional area A=1.71×10⁻⁶m²
The resistivity of copper p=1.72×10⁻⁸Ω
Thus the resistance of extension cord is

Part (b)
The resistance of trimmer Rt=17.9 ohms
When voltage of 120V is applied then the current I is passing through series circuit is

Thus the voltage across the trimmer is:

Answer:
Speed of the this part is given as

Also the direction of the velocity of the third part of plate is moving along 135 degree with respect to one part of the moving plate
Explanation:
As we know by the momentum conservation of the system
we will have

here we know that

the momentum of two parts are equal in magnitude but perpendicular to each other
so we will have


now from above equation we have



Also the direction of the velocity of the third part of plate is moving along 135 degree with respect to one part of the moving plate
It is strong enough to penetrate through flesh but not bone so we can see if there are fractures or breaks in our skeleton