Answer:
dz = 7.136 (answer)
Explanation:
given height for kate's kite = 50 ft (say y)
due to drift it move towards east = dx = 7 ft
string maximum length = 107 ft ( say z)
we have to find change in z
that is dz
it will form a right angle triangle for x , y and z where x is base y is height and z is hypotenuse
so we get according to Pythagoras Theorem
...............(i)
by derivative both side consider y as constant
from (i) equation
now put the value and find dz
after solving these we get
dz = 7.136 (answer)
Concrete is also used as beam material, and is cheaper. However, concrete is comparatively not that strong to withstand the high tensile forces acting on the beams
Answer:
20.4m
Explanation:
72kmhr(1000mkm)(hr3600sec)=20ms
Use principles of conservation of energy.
The initial kinetic energy of the car is equal to the work done by friction during braking:
KE=Wfric
12mv2=(Ffric)d
but the force of friction = weight of the car = mg
12mv2=mgd
mass cancels in both terms, which tells us the answer is independent of mass
12v2=gd
12202=(9.81)d
d=20.4m
Note that the correct answer should actually be 20. m with only 2 significant figure accuracy since 72 km/hr only has 2 sig fig accuracy.
Answer:
D, positive
Explanation:
If displacement is increasing (positive) and time cant be negative. This means that the velocity is increasing.
Hope this helps.