Answer:
- The initial speed of the truck is 21.93 m/s, and the initial speed of the car is 19.524 m/s
Explanation:
We can use conservation of momentum to find the initial velocities.
Taking the unit vector
pointing north and
pointing east, the final velocity will be


The final linear momentum will be:




As there are not external forces, the total linear momentum must be constant.
So:

As initially the car is travelling east, and the truck is travelling north, the initial linear momentum must be
so:
so

So, for the truck





And, for the car



Answer:
D. Half as great
Explanation:
Since we know that the friction force between the surface of crate and ground is given as

so here we know that
= friction coefficient between two surfaces which depends on the effective contact area between two surfaces
= normal force due to the object
So when we turn the object on another side such that the surface area is half then the friction coefficient will become also half
So here the friction force will also reduce to half
so correct answer will be
D. Half as great
Given:
Water 4 m deep
Required:
Pressure at the bottom of the
tank
Solution:
p2 – p1 = gh
p2 – p1 = p = gh
p
= gh =
1000kg/m3 (9.8m/s2)(4m)
<span>p =
39200 Pa</span>
Answer
a)Given,
Wavelength of blue light = 450 n m = 450 x 10⁻⁹ m
Speed of light = 3 x 10⁸ m/s
we know,




b)Given,
Wavelength of red light = 650 n m = 650 x 10⁻⁹ m
Speed of light = 3 x 10⁸ m/s
we know,




At the release point, the ball has kinetic energy,

and at its maximum height it has potential and kinetic energy,

where
is the maximum height attained above the release point.
The LoCoE tells us that we should have



