Answer:
B).315mph
Explanation:
Let the speed of the plane = p
Let the speed of the wind = w
Set up the system equation as;
Relative V: Time: Distance:
in wind direction: p + w 2 700
against wind: p - w 2.5 700
2(p + w) = 700
2.5(p - w) = 700
2p + 2w = 700
2.5p - 2.5w = 700
2.5 x: 5p + 5w = 1750
2 x: 5p - 5w = 1400
10p = 3150
p = 315 mph
Therefore, he speed of the plane in still air is 315 mph
Answer: hello your question is incomplete attached below is the complete question
answer : 1/2 KD^2 ( option A )
Explanation:
P.E ( potential energy ) = mgd
In case 1 P.E = 0 i.e. mgd = 0
Given that in case 2 the Mass M had moved through the Distance D by the compression of the spring
<u>The potential energy of the M in case 2 </u>
= P.E of M at rest + P.E of the spring
= 0 + 1/2 KD^2
Answer:
1,700feet
Explanation:
If an object in free fall travels a distance s that is directly proportional to the square of the time t, this can be represented mathematically as;
S = kt²where;
k is the proportionality constant
K = s/t²
s1/t1²= s2/t2²= Sn/tn²= k for values of the distance and time. Using the formula
s1/t1² = s2/t2² where;
s1 is the falling distance in time t1 s2 is the falling distance in time t2
Given s1 = 1088feet, t1 = 8secs, s2 = ? t2 = 10secs
Substituting this value in the formula to get s2, we have;
1088/8²= s2/10²
64s2= 108800
s2 = 108800/64
s2 = 1,700feet
This means the object will fall a distance of 1,700feet in 10seconds
Answer:
6.65m/s
Explanation:
Using the equation of motion
S = ut + 1/2gt²
S is the height of fall
t is the time
u is the horizontal velocity
g is the acceleration due to gravity
Given
S = 300 + 50
S = 350m
t = 7.8seconds
g = 9.8m/s^2
Get S
S = 7.8u + 1/2(9.8)(7.8)²
S = 7.8u + 298.116
350 = 7.8u + 298.116
7.8u = 350 - 298.116
7.8u = 51.884
u = 51.884/7.8
u = 6.65m/s
Hence the rock's horizontal velocity was 6.65m/s
Answer:
Explanation:
magnetic field B = (3 i + 8 x 2 j )x 10⁻³ T
= (3 i + 16 j )x 10⁻³ T
L = - i ( unit length of conductor )
Force F = I ( L x B ) , I is current
= 5 [ - i x ( 3i + 16 j ) 10⁻³]
= 5 ( - 16 k ) x 10⁻³
F = - 80 x 10⁻³ k