I cant really say but i believe it is called extinction
Answer:
a)W= 1 J
b)W= 1 J
c)W= 0 J
Explanation:
Given that
m = 5 kg
Coefficient of kinetic friction,K=0.5
d= 10 cm
We know that if velocity is constant it means that the acceleration of the system is zero.Or we can say that all forces are balance in the system.
We know that work is the dot product of force and displacement
W= F.d
The friction force on the box
Fr= K m g
Fr= 0.5 x 5 x 10 = 25 N ( take g =10 m/s²)
Fr=25 N
a)
Acceleration a= 0
So horizontal force F = Fr
W = Fr.d
W=10 x 0.1 J
W= 1 J
b)
The work done by friction force
W= 1 J
c)
The net force on the system is zero because acceleration is zero.
F= 0
So
W= 0 J
Answer:
d.
Explanation:
Since the dart's initial speed v at angle has both vertical and horizontal components v₀sinθ and v₀cosθ respectively, the vertical component of the speed continues to decrease until it hits the target. It's displacement ,s is gotten from
s = y - y₀ = (v₀sinθ)t - 1/2gt² where y₀ = 0 m
y - 0 = (v₀sinθ)t - 1/2gt²
y = (v₀sinθ)t - 1/2gt²
which is the parabolic equation for the displacement of the dart.
Note that the horizontal component of the dart's velocity does not change during its motion.
Since the target falls vertically, with initial velocity u = 0 (since it was stationary before the string cut), it's displacement ,s' is gotten from
s' = y - y₀' = ut - 1/2gt² where y₀' = initial height of target above the ground
= (0 m/s)t - 1/2gt²
= 0 - 1/2gt²
y - y₀' = - 1/2gt²
y = y₀' - 1/2gt²
which is the parabolic equation for the displacement of the target.
The equation for both the displacement of the dart and the target can only be gotten if we considered vertical motion. So, the displacement component of both the dart and target are both vertical.
So, the answer is d.
Tetrahedron is a geometrical figure or solid that is formed in similar manner as a pyramid. The faces of the formed pyramid are triangles. Also is the base.
By the statement above, it can be deduced that the figure has four sides. The number of ways in which the sides can be colored by any of the three (3) colors is,
3 x 3 x 3 x 3 = 81
Since the sides can still have the same colors, we deduct this value by 3 in order to eliminate the uniform colors of the four sides.
= 81 - 3 = 78
Also, we can eliminate the concern on only two colors can mix,
= 3 x 2 = 6
Subtracting,
78 - 6 = 72
Hence, the answer is 72.
