Answer:
Explanation:
F = ma. For us, this looks like
60 = 30a and
a = 2 m/s/s
If the force goes up to, say, 90, then
90 = 30a and
a = 3...if the force goes up, the acceleration also goes up.
If the mass goes up to say, 60, and the force stays the same, then
60 = 60a and
a = 1...if the mass goes up, the acceleration goes down.
Answer:
<h3>The answer is 5.4 kg</h3>
Explanation:
The mass of the object can be found by using the formula

f is the force
a is the acceleration
From the question we have

We have the final answer as
<h3>5.4 kg</h3>
Hope this helps you
Answer:
30.63 m
Explanation:
From the question given above, the following data were obtained:
Total time (T) spent by the ball in air = 5 s
Maximum height (h) =.?
Next, we shall determine the time taken to reach the maximum height. This can be obtained as follow:
Total time (T) spent by the ball in air = 5 s
Time (t) taken to reach the maximum height =.?
T = 2t
5 = 2t
Divide both side by 2
t = 5/2
t = 2.5 s
Thus, the time (t) taken to reach the maximum height is 2.5 s
Finally, we shall determine the maximum height reached by the ball as follow:
Time (t) taken to reach the maximum height = 2.5 s
Acceleration due to gravity (g) = 9.8 m/s²
Maximum height (h) =.?
h = ½gt²
h = ½ × 9.8 × 2.5²
h = 4.9 × 6.25
h = 30.625 ≈ 30.63 m
Therefore, the maximum height reached by the cannon ball is 30.63 m
Answer:

Explanation:
By Einstein's Equation of photoelectric effect we know that

here we know that
= energy of the photons incident on the metal
= minimum energy required to remove photons from metal
= kinetic energy of the electrons ejected out of the plate
now we know that it requires 351 nm wavelength of photons to just eject out the electrons
so we can say

here we know that

now we have

now by energy equation above when photon of 303 nm incident on the surface





Answer:
7.72 Liters
Explanation:
normal body temperature = T_body =37° C
temperature of ice water = T_ice =0°c
specfic heat of water = c_{water} =4186J/kg.°C
if the person drink 1 liter of cold water mass of water is = m = 1.0kg
heat lost by body is Qwater =mc_{water} ΔT
= mc{water} ( T_ice - T_body)
= 1.0×4186× (0 -37)
= -154.882 ×10^3 J
here negative sign indicates the energy lost by body in metabolic process energy expended due to brisk - hour long walk is Q_{walk} = 286 kilocalories
= 286×4186J
so number of liters of ice water have to drink is
n×Q_{water} =Q_{walk} n= Q_{walk}/ Q_{water}
= 286×4186J/154.882×10^3 J
= 7.72 Liters