Answer:the answer is D
Explanation:
Plug variables in and calculate
Answer: Speed = 4m/s
Strength = 7.1T
Explanation: P= 4.0w
N = 1.0
V= ?
Power = force x velocity
Velocity = power/ force
V= 4.0w/1.0N
V = 4m/s
Strength of the magnetic field
B = √PR / lv
Where; l = length 10cm
R= 2.0
P= 4.0w
V= 4m/s
B = √ (4.0w) × (2.0) / (10cm) × (4m/s)
B = 7.1T
<span>a) M is the big one
m is the little one
v is the speed of each of them when they impact
V = speed of mii after collision
Conservation of momentum
Mv – mv = mV
Conservation of energy
1/2Mv^2 + 1/2mv^2 = 1/2 mV^2
This pair simplify to give
M = 3m
V = 2v
So m = 0.21kg
and h = 4 . 2.7 = 10.8 m</span>Source(s):<span>Old teacher</span>
Answer:
(a) 8.117 (b) 0.742
Explanation:
We have given distance s =40 m time t=7.5 sec
Final velocity v =2.55 m/sec
From the first equation of motion 
(negative sign because there is retrdation as the truck speed is slowing down )
So 
--------------eqn 1
From the second equation of motion 
( negative sign because there is retrdation as the truck speed is slowing down )
So 
------------------eqn 2
On solving eqn1 and eqn 2
u=8.117 m/sec and a=-0.742
Yes because something that has been electrically charged can make other things move without touching them ( this is called force without contact)
Hoped this helped :)
