When driver see the child standing on road his speed is 20 m/s
So here at that instant his reaction time is 0.80 s
He will cover a total distance given by product of speed and time
now after this he will apply brakes with acceleration a = 7 m/s^2
so the distance covered before it stop is given by
so the total distance covered by it
<em>so it will cover a total distance of 44.6 m</em>
Answer:
41°
Explanation:
Kinetic energy at bottom = potential energy at top
½ mv² = mgh
½ v² = gh
h = v²/(2g)
h = (2.4 m/s)² / (2 × 9.8 m/s²)
h = 0.294 m
The pendulum rises to a height of above the bottom. To determine the angle, we need to use trigonometry (see attached diagram).
L − h = L cos θ
cos θ = (L − h) / L
cos θ = (1.2 − 0.294) / 1.2
θ = 41.0°
Rounded to two significant figures, the pendulum makes a maximum angle of 41° with the vertical.
Answer:
The temperature of the metal is
Explanation:
From the question we are told that
The mass of the metal is
The specific heat of the metal is
The mass of the oil is
The temperature of the oil is
The specific heat of oil is
The equilibrium temperature is
According to the law of energy conservation
Heat lost by metal = heat gained by the oil
So
The quantity of heat lost by the metal is mathematically represented as
=>
Where the temperature of metal before immersion
The negative sign show heat lost
The quantity of gained t by the metal is mathematically represented as
=>
So
substituting values
=>