Answer:
i. 7.5 m
ii. 15000 N
Explanation:
Area under vt graph shows the displacement
so area of triangle ABE= 1/2×15×2
=7.5 m
ii) F=ma
here, m=1000kg
and a=v-u/t
=15-0/1
a=15
F=1000×15=15000N
Answer:
Magnetic field, B = 0.275 T
Explanation:
Given that,
Length of the wire, L = 35 cm = 0.35 m
Current carried in the wire, I = 2.6 A
The segment makes an angle of 53∘ with the direction of the magnetic field, 
Magnetic force, F = 0.2 N
To find,
The magnitude of the magnetic field.
Solution,
The magnetic force acting on the wire is given by :

is the angle between the length of wire and the magnetic field.

B = 0.275 T
Therefore, the magnitude of the magnetic field is 0.275 T. Hence, this is the required solution.
Answer:
6.77 minutes
Explanation:
172 degree - 78 degree = (185 degree - 78 degree)e−2 k
=> 94 = 107
e−2 k => 94 ÷ 107
k => ln (94÷107) / 2
147 - 78 = (185 - 78)e ^[ln (94÷107) / 2]
=> 69 = 107 e^ [ln (94÷107) / 2]
e^[ln (94÷107) / 2] =69 ÷ 107
=> t = [ln (69 ÷ 107)] ÷ [ln (94÷107) / 2]
t=> -0.4387 ÷ -0.0648
t => 6.77 minutes.
Therefore, the final answer to the question is 6.77 minutes.
The true statements are B and C.
This comes from the following facts:
Even when heat is added to a substance in a change of phase the temperature does not increases since this heat is latent heat.
Answer:
t = 0.354 hours
Explanation:
given,
coefficient of rolling friction μr=0.002
mass of locomotive = 180,000 Kg
rolling speed = 25 m/s
The force of friction = μ mg
= (.002) x (180000) x (9.8)
= 3528 N
F = m a
now,
m a = 3528 N
180000 x a = 3528
a = 0.0196 m/s²
Then apply
v = u + at
0 = 25 - 0.0196 x t
t = 1275.51 sec
t = 1275.61/3600 hours
t = 0.354 hours
time taken by the locomotive to stop = t = 0.354 hours