Any transparent material that allows light of only certain color to pass through is called a filter . true or false

James Bond is trying to escape his enemy on a speedboat but

SVEN [57.7K]

Answer:

100 m/s

Explanation:

Mass the mass of Bond's boat is m₁. His enemy's boat is twice the mass of Bond's i.e. m₂ = 2 m₁

Initial speed of Bond's boat is 0 as it won't start and remains stationary in the water. The initial speed of enemy's boat is 50 m/s. After the collision, enemy boat is completely stationary. Let v₁ is speed of bond's boat.

It is the concept of the conservation of momentum. It remains conserved. So,

$m_1u_1+m_2u_2=m_1v_1+m_2v_2$

Putting all the values, we get :

$0+(2m_1)50=m_1v_1+(2m_2)(0)\\\\100m_1=m_1v_1\\\\v_1=100\ m/s$

So, Bond's boat is moving with a speed of 100 m/s after the collision.

3 0

4 years ago

A truck enters a typical runaway lane with a speed of 57.5 mph ( 25.7 m/s ). Use the work-energy theorem to find the minimum coe

Helen [10]

Answer:

Work done by friction force= change in total Energy

so,

W= (friction force)*d= (mu*N)*(35)

so,

mu*m*g*35= 1/2*m*v^2

so,

mu= 0.5*(25.7)^2/(9.81*35)

solving it,

mu = 0.9618

Explanation:

4 0

3 years ago

A plank rests on top of the axles of two identical wheels. Each wheel's outer radius is 0.25 meters and each wheel's axle has ra

kaheart [24]

Answer:

The plank moves 0.2m from it's original position

Explanation:

we can do this question from the constraints that ,

the wheel and the axle have the same angular speed or velocity
the speed of the plank is equal to the speed of the axle at the topmost point .

thus ,

since the wheel is pure rolling or not slipping,

⇒ $v=wr$

where

$v$ - speed of the wheel

$w$ - angular speed of the wheel

$r$ - radius of the wheel

since the wheel traverses 1 m let's say in time ' $t$ ' ,

$v_{w}=\frac{distance}{time} =\frac{1}{t}$

∴

⇒ $w=\frac{v_{w}}{r} = \frac{1}{t*0.25}$

the speed at the topmost point of the axle is :

⇒ $v_{a}=w*r\\v_{a}=\frac{1}{t*0.25} *0.05\\v_{a}=\frac{1}{5t}$

this is the speed of the plank too.

thus the distance covered by plank in time ' $t$ ' is ,

⇒ $d=v_{a}*t\\d=\frac{1}{5t} *t\\d=\frac{1}{5} = 0.2m$

8 0

4 years ago

1. Calculate the charge in a circuit which carries a current of 30 amperes for 5 seconds

sweet-ann [11.9K]

Answer:

1. 150C.

2. 50sec

3.1.5a

Explanation:

1. I = Q/T

Q= 30x5

=150c

2.applying the formulae, I = Q/T

T= Q/I

=500/10

=50sec.

3. using the formulae i=q/t

i= 120/80

=1.5a.

6 0

3 years ago

A car of mass 775 kg traveling at a velocity of 30 m/s in the positive x-direction crashes into the rear of a truck of mass 1,47

Thepotemich [5.8K]

Answer:

velocity of the car is 7.3516 m/s

Explanation:

M1v1a + m2v1b = m1v2a + m2v2b

775*30 + 1475*0 = 775*v2a+1475*11.9

Let v2a be x

23250 + 0 = 775x + 17552.5

775x = 23250-17552.5

775x = 5697.5

X = 7.3516 m/s

4 0

3 years ago