The acceleration of the skydiver is given by:
where
is the final velocity of the skydiver
is the initial velocity of the skydiver
is the time taken for the change of speed
Substituting the numbers into the equation, we find the skydiver's acceleration:
where the negative sign means it is a deceleration.
Answer a) impulse is 1360 kg.m/s
Explanation: impulse is impact force times the time of impact
I = 3400 * 0.4 = 1360kg.m/s
Answer b) final velocity is 10.1m/s
Explanation: impulse is the change of momentum
I = m(v-u)
V and u are final and initial velocities respectively.
1360 = 200 (v - 3.3)
1360 = 200v - 660
V = (1360+660)÷200
V = 10.1m/s
Q2 answer is: astronaut has KE approximately 208 times that of the truck
Explanation :
KE = 0.5mv^2
For truck
KE = 11000 * 33.3^2 = 12197790J
For astronaut
KE = 42 * 7777.7^2 = 2540689926J
Comparing
2540689926/12197790 = 208.2
NB: speed has been converted to m/s by multiplying with 0.28 I.e 1000/3600
Answer:
B_2 / B_1 = 0.5 , Half of magnetic field at distance d.
Explanation:
Given:
- A current carrying conductor produces a magnetic field = B_1 @ r = d
- A current carrying conductor produces a magnetic field = B_2 @ r = 2*d
Find:
Compare the the magnetic Field at two points r = d and r = 2*d:
Solution:
- The magnetic Field of long current carrying wires are expressed as follows:
B = u_o*I / 2*pi*r
Where,
B = Magnetic Field
I = The current in the conductor
r = The radial distance from the center of the wire.
u_o = Permittivity of free space (constant)
- Now compute B_1 and B_2:
B_1 = B = u_o*I / 2*pi*d
B_2 = B = u_o*I / 4*pi*d
- Take a ratio of B_2 to B_1:
B_2 / B_1 = (u_o*I / 4pi*d) * ( 2*pi*d/u_o*I)
B_2 / B_1 = 0.5
- Hence, the magnetic field at distance 2d is half of the magnetic field at distance d.
Answer:
The speed of the truck is 14.95 m/s.
Explanation:
Given that,
Radius = 44.2 m
Coefficient of static friction = 0.516
We need to calculate the speed of the truck
Using relation of frictional force and centripetal force
Where, r = radius
g = acceleration due to gravity
v = speed
Put the value into the formula
Hence, The speed of the truck is 14.95 m/s.