Answer:
t=0.42s
Explanation:
Here you have an inelastic collision. By the conservation of the momentum you have:

m1: mass of the bullet
m2: wooden block mass
v1: velocity of the bullet
v2: velocity of the wooden block
v: velocity of bullet and wooden block after the collision.
By noticing that after the collision, both objects reach the same height from where the wooden block was dropped, you can assume that v is equal to the negative of v2. In other words:

Where you assumed that the negative direction is upward. By replacing and doing v2 the subject of the formula you get:

Now, with this information you can use the equation for the final speed of an accelerated motion and doing t the subject of the formula. IN other words:

hence, the time is t=0.42 s
Refer to the diagram shown below.
h = the height of the building
g = 9.8 m/s²
Wind resistance is ignored.
u = 22.2 m/s, horizontal velocity.
The initial vertical velocity is zero.
The time of flight, t, obeys the equation
h = (1/2)*g*t²
That is,
h = 0.5*(9.8 m/s²)*(t s)² = 4.9t²

Because the horizontal distance traveled is 36.0 m, therefore
(22.2 m/s)*(0.4518√h) = 36.0
10.03√h = 36
√h = 3.5892
h = 12.882 m
Answer: 12.9 m (nearest tenth)
Answer:
9.44 eV
Explanation:
q = Amount of charge = 86.3 μC = 86.3 x 10⁻⁶ C (Since 1 μC = 10⁻⁶ C)
V = Electric potential of the charge = 17.5 Volts
U = Amount of electric potential energy carried by charge
Amount of electric potential energy carried by charge is given as
U = q V
Inserting the values
U = (86.3 x 10⁻⁶) (17.5)
U = 0.00151 J
U = 
U = 9.44 eV
KE = Kinetic energy the charge could have
Using conservation of energy
KE = U
KE = 9.44 eV
Answer:
c) wafers of crystalline silicon treated with metals that absorb solar radiation and generate electricity
Explanation:
Photovoltaic solar cells are used in solar panels. Most of the photovoltaic cells are made from crystalline silicon.
It has a property using which it converts the light (solar radiation) falling on it to electrical energy. This process occurs due to the photovoltaic effect.
It is a way generating energy without consuming fossil fuels. Thus it reduces the carbon emission and thus plays a major role in environment protection.
Answer:

Explanation:
First we need to state our assumptions:
Thermal properties of ice and water are constant, heat transfer to the glass is negligible, Heat of ice 
Mass of water,
.
Energy balance for the ice-water system is defined as

a.The mass of ice at
is defined as:
![[mc(0-T_1)+mh_i_f+mc(T_2-0)]_i_c_e+[mc(T_2-T_1)]_w=0\\\\m_i_c_e[0+333.7+418\times(5-0)]+0.3\times4.18\times(5-20)=0\\m_i_c_e=0.0546Kg=54.6g](https://tex.z-dn.net/?f=%5Bmc%280-T_1%29%2Bmh_i_f%2Bmc%28T_2-0%29%5D_i_c_e%2B%5Bmc%28T_2-T_1%29%5D_w%3D0%5C%5C%5C%5Cm_i_c_e%5B0%2B333.7%2B418%5Ctimes%285-0%29%5D%2B0.3%5Ctimes4.18%5Ctimes%285-20%29%3D0%5C%5Cm_i_c_e%3D0.0546Kg%3D54.6g)
b.Mass of ice at
is defined as:
![[mc(0-T_1)+mh_i_f+mc(T_2-0)]_i_c_e+[mc(T_2-T_1)]_w=0\\\\m_i_c_e[2.11\times(0-(20))+333.7+4.18\times(5-0)]+0.3\times4.18\times(5-20)=0\\\\m_i_c_e=0.0487Kg=48.7g](https://tex.z-dn.net/?f=%5Bmc%280-T_1%29%2Bmh_i_f%2Bmc%28T_2-0%29%5D_i_c_e%2B%5Bmc%28T_2-T_1%29%5D_w%3D0%5C%5C%5C%5Cm_i_c_e%5B2.11%5Ctimes%280-%2820%29%29%2B333.7%2B4.18%5Ctimes%285-0%29%5D%2B0.3%5Ctimes4.18%5Ctimes%285-20%29%3D0%5C%5C%5C%5Cm_i_c_e%3D0.0487Kg%3D48.7g)
c.Mass of cooled water at 

![[mc(T_2-T_1)]_c_w+[mc(T_2-T_1)]_w=0\\m_c_w\times4.18\times(5-0)+0.3\times4.18\times(5-20)\\m_c_w=0.9kg=900g](https://tex.z-dn.net/?f=%5Bmc%28T_2-T_1%29%5D_c_w%2B%5Bmc%28T_2-T_1%29%5D_w%3D0%5C%5Cm_c_w%5Ctimes4.18%5Ctimes%285-0%29%2B0.3%5Ctimes4.18%5Ctimes%285-20%29%5C%5Cm_c_w%3D0.9kg%3D900g)