The hashrate is the rate at which hashes of a block are being solved. The more miners join a cryptocurrency network, the higher the network hashrate is. The higher the Bitcoin price the more miners are incentivized to mine Bticoin thus higher the hashrate. It isn’t true vice versa. Adding more hashrate doesn’t increase the price of Bitcoin but it makes Bitcoin more secure. The amount of electricity used by miners is embedded in the blockchain. An attacker would have to spend more energy than the rest of the miners combined. When the price of Bitcoin falls miners lose profit and don’t have financial incentive to mine. The hashrate falls when miners leave. Less miners means lower competition, thus profitability of remaining miners increase and bringing back equilibrium.